PV Installer Program-Participant Guide

8/15/2019 PV Installer Program-Participant Guide

http://slidepdf.com/reader/full/pv-installer-program-participant-guide 1/238





Solar Energy is a Electro Magnetic

Wave Radiation

• Radi ation emanated from the sun at a temperature of 5000 o K

• Magnetic Wave travels a distance of 1.5 * 10 8 km

• The Sun subtends and angle of 32’ with the earth

• Solar Constant i.e. Sola r Radiation of 1395 W / m 2 in space

Electro Magnetic Wave Radiation

• Gamma Rays 10 – 8 to 10 – 4 µ m

• X – rays 10 – 5 to 10 – 2 µ m

• Ultraviolet 10 – 2 to 1 µ m

• Visible Spectrum 0.38 to 0.78 µ m

• Thermal Radiation – near infrared and far infrared 1 to 10+ 3

µm

• Radar, T V and Radio 10 + 3 to 10 + 10µ m



Azimuth angle of the sun:

Often def ined as the angle f rom due north in a c lockwise direction. (sometimes f rom south)

Zenith angle of the sun:

Def ined as the angle measured f rom vertical downward.

Position of the Sun

Path of the Sun



Declination = 23.45 * Si n (360*(284+n)/365)

Opti mum Ti lt angle = Latitude

for the ma ximum collection through out the year

§ Season Optimization tilt = (Latitude - Declination)

Elevation and Azimuth

Cos θZ = Sin δ * Sin φ + Cos δ * Cos φ * Cos ω

α = 90 - θZ

Solar Path Diagram

http://andrewmarsh.com/blog/2010/01/04/solar-position-and-sun-path

2/6/201

38 Corporate Communication













Horizontal & Vertical Shadow

http://andrewmarsh.com/blog/2010/01/10/horizontal-and-vertical-shadow-angles

2/6/201















Solar Radiation

Global

Direct

Diffused

Global = Direct + Diffused







© 2011 Underwriters Laboratories Inc.

Photovoltaic

n-typesemiconductor

p-typesemiconductor

+ + + + + + + + + + + + + + + - - - - - - - - - - - - - - - - - -

Physics of Photovoltaic Generation

Depletion Zone



How PV Cell produce Electricity:

► When rays of sunlight hit the solar cell electrons are ejectedfrom the atoms.

► Electrons are knocked loose from their atoms, which

allow them to flow through the PN Junction to

produce electricity.

Working of Solar Cell Video

20





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http://carry-display.en.alibaba.com/product/369865568-210713719/6_5inch_monocrystal_silicon_sheet.html?tracelog=cgsotherproduct4

http://carry-display.en.alibaba.com/product/364345621-210713719/125_single_monocrystal_silicon_sheet.html?tracelog=cgsotherproduct4









2/6/201


2/6/201




Solar PV Markets Capacity installed in 2011

33

34



35

36



37

38



2

39

40



2

PV Module Production, Supply, and Demand

Metrics

41

42



2

2/6/201


1,920.00

1,940.00

1,960.00

1,980.00

2,000.00

2,020.00

2,040.00

2,060.00

a-si Cd-Te CIS Mono-si Poly -si HIT

1,990.20

2,028.60

2050.7 2,053.10 2053.1

1966.4

E l e c t r i c i t y E x p o r t e d t o

T h e

G r i d ( M W h ) F o r F i x e d

T i l t

Output vs Technology at Leh, Jammu & Kashmir State

1,600.0

1,650.0

1,700.0

1,750.0

1,800.0

1,850.0

1,900.0

1,950.0

a-si Cd-Te CIS Mono-si Poloy-si HIT

1,862.5

1,820.4

1,712.0

1,750.0 1,750.0

1,905.2

E l e c t r i c i t y E x p o r t e d t o T h e

G r i d ( M W h ) F o r F i x e d T i l t

Output vs Technology at Bangalore, KarnatakaState

1,600.0

1,650.0

1,700.0

1,750.0

1,800.0

1,850.0

1,900.0

1,950.0


1,879.4

1,830.4

1,710.1

1,751.5 1,751.5

1,928.0


G r i d

( M W h ) F o r F i x e d T i l t

Output vs Technology at Bellary, Karnataka State

1,550.0

1,600.0

1,650.0

1,700.0

1,750.0

1,800.0

1,850.0

1,900.0

1,950.0


1,866.6

1,814.7

1,690.0

1,732.5 1,732.5

1,917.5



Output vs Technology at Charanka, Gujarat State

1,600.0

1,650.0

1,700.0

1,750.0

1,800.0

1,850.0

1,900.0

1,950.0


1,893.1

1,845.1

1,726.0

1,767.2 1,767.2

1,941.0



Output vs Technology at Jaisalmer, Rajasthan State

BangaloreCharanka

Leh

0.0500.0

1,000.01,500.02,000.02,500.0

a-si CdTe

CIS Mono-si

Poly-si

HIT

Bangalore 1,8621,8201,7121,7501,7501,905

Brllary 1,8791,8301,7101,7511,7511,928

Charanka 1,8661,8141,6901,7321,7321,917

Jaisalmer 1,8661,8141,6901,7321,7321,917

Leh 1,9902,02820512,05320531966

E l e c t r i c i t y E x p o r t e d t o t h e G r i d

( M W h )

Output vs Technology for Fixed Tilt

2/6/201


0.0

10.0

20.0

30.0

40.0

a-si CdTe CIS Mono-si Poly -si HIT

21.0 21.3 21.7 21.5 21.5 20.9

30.4 30.3 30.2 30.3 30.3 30.4

35.4 35.2 34.9 35.0 35.0 35.5

P e r c e n t a g e

I n c r e a s e i n O u t p u t

Percentage Increase vs Technology at Leh, Jammu &Kashmir

One-axis

Polar

Two-axis

0.0

10.0

20.0

30.0


22.5 22.6 22.8 22.7 22.7 22.4

24.0 24.0 23.9 23.9 23.9 24.027.4 27.3 27.1 27.2 27.2 27.5

P e r c e n t a g e I n c r e a s e i n O u t p u t

Percentage Increase vs Technology at Bangalore,Karnataka

One-axisPolarTwo-axis

0.0

10.0

20.0

30.0


22.1 22.3 22.6 22.4 22.4 22.0

24.3 24.3 24.3 24.3 24.3 24.4

27.9 27.8 27.6 27.7 27.7 28.0


Percentage Increase vs Technology at Bellary,Karanataka


0.0

10.0

20.0

30.0


21.0 21.2 21.6 21.4 21.4 20.9

25.5 25.5 25.5 25.5 25.5 25.5

29.4 29.3 29.0 29.1 29.1 29.5


Percentage Increase vs Technology at Charanka, GujaratOne-axisPolarTwo-axis

0.0

10.0

20.0

30.0

40.0


21.5 21.7 22.1 21.9 21.9 21.3

26.8 26.8 26.7 26.8 26.8 26.8

30.9 30.7 30.4 30.5 30.5 31.0

P e r c e n t a g e

I n c r e a s e i n O u t p u t

Percentage Increase vs Technology at Jaisalm er,Rajasthan






2

THANK YOU.




Inspection Plan of

Civil Foundations

for Solar Power Plants

IS 1498:1970 – Classification & identification of soils for Engineering purposes

IS: 1199 – 1959 – Tes ts on fresh concrete

IS: 13311 (Part 1,2) – 1992 – Tes ts on hardened concrete

IS 516:1959 – Me thods of tests for strength of concrete

IS: 2720 (Part II) – 1973 – Tests on soil – To determine w ater content in s oil

IS: 2720 (Part 4) – 1985 - To de termine the particle size distribution of soil

IS: 2720 (Part 5) –

1985-To determine the liquid limit and plastic limit of soil

IS: 2720 (Part 8) – 1983 - To determine the maximum dry density and the

optim um moisture content of soil

Standard References



Contents:

Introduction to soil types for foundations

Introduction to foundations

Foundations types used for Solar power plants

3


Introduction to Soil

types for Foundations



55

Soil Map of INDIA:

What is Soil?

6

Mineral45%

Air25%

Water25%

Organics5%



7

GRAVEL SAND

ClaySilt

Minerals

8

Soil Groups

Soil Type Gradation Plasticity

Gravel – G

Sand – S

Silt – M

Clay – C

Organic – O

Well Graded – W

Poorly Graded – P

High Plasticity – H

Low Plasticity – L

Soil type & particle size distribution as follows:

• Gravel : 80 –

4.75 mm

• Sand : 4.75mm – 0.075mm (75 micron)

• Silt : 75 – 2 micron

• Clay : less than 2 micron



99

Soil Type Allowable Bearing(lb/ft2 - Pound per square foot )

Drainage

BEDROCK 4,000 to 12,000 Poor

GRAVELS 3,000 Good

SAND 2,000 Good

SILT 1,500 Medium

CLAY 1,500 Medium

ORGANICS 0 to 400 Poor

Estimated Soil Load Bearing Capacities

1010101010

Soil Layers:

10



11

Sand and gravel –

Best

Medium to hard clays – Good

Soft clay and silt – Poor

Organic silts and clays – Undesirable

Peat – No Goo d / Avo id

Peat i s an a ccum ulat ion of p art ial ly decayed vegetat ion matter or o rganic

mat ter .

Soil Strength Classification for Foundations

Laboratory tests for Soil

Following laboratory tests are to be carr ied out to determine the physical and

engineering properties of soil samples:

1. Dry de nsity and moisture content - (IS 2720 part – 2 & 29)

2. Particle size analysis - (IS 2720 part – 4:1985)

3. Specific gravity - (IS 2720 part – 3/se c2:1980)

4. Shear test - (IS 2720 part – 11:1986)

5. Consolidation test - (IS 2720 part – 15:1986)

6. Free swell test - (IS 2720 part – 40:1977 & 41:1977)

7. Consistency Limits

8. Che mical Analysis of representative soil samples

12



Soil Samples

Disturbed samples: which do not represent exactly how the soil was in itsnatural state before sampling.

Disturbed samples are used for the more simple tests that will be

performed and particularly for those tests which can be performed byself in the field.

Undisturbed samples: which represent exactly how the soil was in itsnatural state before sampling.

Undisturbed samples are necessary for the more sophisticated testswhich must be performed in the laboratory for more detailed physical

and chemical

analyses. Undisturbed samples must be collected with greater care for

they should represent exactly the nature of the soil.

13

Sample Soil Test Report

14




Introduction to Foundations

16

The soil beneath the structures responsible for carrying the loads iscalled FOUNDATION.

The general misconception is that the structural element which transmits

the load to the soil(such as a footing) is the foundation. The figure belowclarifies this point.

Definition of foundation



Forces acting onto Foundation

17

18

Classification of Foundations

Shallow foundations are placed at a shallow depth beneath the soil

surface. They include footings and soil retaining structures. The depth is

generally less than the width of the footing and less than 3m.

Shallow Foundations

Deep Foundations

Deep foundations are commonly using piles. They are embedded verydeep into the soil. They are usually used when the top soil layer have low

bearing capacity. Deep foundations are usually at depths deeper than 3m.



19

Footing

Footing

20

Df

B

Footing

Ground Surface C o l u m n

P

For Shallow Foundation = Df < 4B

Shallow Foundation

P - Normal load



21

Pile

Hammer

Shaft

Pre

bored

hole

Poured in place fill

Deep Foundations

Ground Surface

Df

B

For Deep Foundation = Df > 4B

22

Laboratory tests for Concrete foundations

Tests on Fresh Concrete -

1. Slump test: To determine the strength of fresh concrete by slumptest as per IS: 1199 - 1959.

2. Compacting factor test: To determine the strength of fresh concrete

by compacting factor test as per IS: 1199 - 1959.

3. Vee-Bee test: To determine the strength of fresh concrete by usinga Vee-Bee consistometer as per IS: 1199 - 1959.



2323

Laboratory tests for Concrete foundations

Tests on Hardened Concrete:

1. Non-destructive tests

a. Rebound hammer test: To assess the likely compressive strengthof concrete by using rebound hammer as per IS: 13311 (Part 2) - 1992.

b. Ultrasonic pulse velocity test: To assess the quality of concreteby ultrasonic pulse velocity method as per IS: 13311 (Part 1) - 1992.

2. Compression test(Destructive): To determine the compressivestrength of concrete specimens as per IS: 516 – 1959.

Clear horizontal distance between reaction supports

and test foundation

24

a) For pad and chimney, grillages, concrete block foundations or

buried anchors:

L = e + 0,7 x a (m)

Where,

e is the width of foundation in metres;

a is the depth of foundation in metres;

L is the distance between nearest points of reaction supports.

b) For concrete piers, driven piles, drilled and grouted piles, or helixanchors:

L = 3 x e (m)



Figures:

25

Sample Concrete Test Report

26



Types of PV Foundation used for Solar Power Plants:

This includes any of the following foundations:

Concrete pier

Driven post

Screw piles

Precast or cast-in-place concrete ballast

27

Concrete pier

o Make sure the bottom of the footing rests on undisturbed soil

free of organic material.

28

o Uses reinforcing bar to firmly

connect the footing at the base

to the concrete pier.

o At the top, a metal post base

connects the concrete pier to the

mounting structure.



Driven pile systems

29

Driven pile systems are often found to be the more favorablechoice based on cost, installation time, materials, and

environmental impact.

Screw piles

• Screw piles are a steel

screw-in piling and ground

anchoring system used for

structure foundations.

30

• The pile shaft transfers a

structure's load into the

pile.

• Screw piles are also

known as ground screws



Screw piles or Ground screws

Helical steel plates are welded to the pile shaft in accordance withthe intended ground conditions.

31

Precast or cast-in-place concrete ballast

Ballasted footings are designed for mounting photovoltaic

solar panels quickly.

Capable of relocation and reuse, the footings are intended for

use in demanding applications, where panels need to be

secured in unstable, environmentally sensitive, or impenetrable

ground conditions.

32



Pile Foundation for Solar PV - Video

33

34

Ground Screw for Solar PV - Video




THANK YOU




Solar Photovoltaic (PV)

System and Safety Measures

1


Key Elements of a PV System

2

loadEnergy

source

power

conditioning

Energyconversion

Inverter

Charge

Controller

PV Array

Energy

distribution

load

center

Battery

Energy

storage

Electric

utility

network



3

Solar PV Safety involves

1. Working safely with photovoltaic systems

2. Conducting a site assessment

3. Selecting a system design

4. Adapting the mechanical design to the site

5. Adapting the electrical design to the site

6. Installing subsystem & components at site

7. Performing a system checkout and inspection

8. Maintaining and troubleshooting the system

4

OSHA* Safety Categories

> Personal Protection Equipment (PPE)

> Electrical

> Falls

> Stairways and Ladders

> Scaffolding

> Power Tools> Materials Handling

> Excavation

* - Occupational Safety & Health Administration



5

Personal Protection Equipment (PPE)

6

Personal Protection Equipment

Responsibilities

EmployerAssess workplace for hazards.

Provide personal protective equipment (PPE).

Determine when to use.

Provide PPE training for employees and instruction in properuse.

EmployeeUse PPE in accordance with training received and otherinstructions.

Inspect daily and maintain in a clean and reliable condition.



7

Examples of PPE

Eye Safety Glasses, Goggles

Face Face Shields

Head Hard Hats

Feet Safety Shoes

Hands and arms Gloves

Bodies Vests

Hearing Earplugs, Earmuffs

Body Part Protection

Equipment

8

Eye Protection



9

Preventing Electrical Hazards:

PPE

Proper foot protection (not

tennis shoes)

Hard hat(insulated -

nonconductive)

Rubber insulating gloves,

hoods, sleeves, matting, and

blankets

10

Selecting the Right Hard Hat

Class A

>General service (building construction, ship building,

lumbering)

> Good impact protection but limited voltage protection

Class B

> Electrical/utility work

> Protects against falling objects and high-voltage shock and

burns

Class C

> Designed for comfort, offers limited protection

> Protects against bumps from fixed objects, but does not

protect against falling objects or electrical shock



11

Hand Protection

12

Electrical Injuries

There are three main types of

electrical injuries:

> Electrocution or death due to

electrical shock

> Severe burns

> Falls (caused by shock)



13

Dangers of Electrical Shock

> Currents above 10 mA* can paralyze or

“freeze” muscles.

> Currents more than 75 mA can cause a

rapid, ineffective heartbeat & death will

occur in few minutes unless a

defibrillator is used.

> 75 mA is not much current – a small

power drill uses 30 times as much.

* mA = milliampere = 1/1000 of an ampere

14

Personal FallArrest System

(PFAS)

Guardrails Safety Net

Fall Protection Options



15

Must be independent ofany platform anchorage

and capable of

supporting at least 5,000

pounds (2268 kg)

Safety Line Anchorages

16

Ladder Angle

Non-self-supporting ladders

(that lean against a wall or

other support):

Position at an angle where

the horizontal distance from

the top support to the foot of

the ladder is 1/4 the working

length of the ladder.



17

Grounding

> Grounding creates a low-

resistance path from a tool to

the earth to disperse unwanted

current.

> When a short or lightning

occurs, energy flows to the

ground, protecting you from

electrical shock, injury and

death.

18

Improper Grounding

>Tools plugged into improperly

grounded circuits may become

energized.

>Broken wire or plug on

extension cord

*Some of the most frequently

violated OSHA standards



Unsafe Installation Practices - Photos

19

20

Unsafe Installation Practices - Photos



THANK YOU




Site Selection, Resource Assessment

&

Energy Yield Estimation

Photovoltaic System



Site Selection

3

Good Layout

Good LayoutsHapezoidal Layouts



Improper Site Selection

Plan for Rock

Blasting



Compromising With

Placing Modules

Embanking Soil to Level The Site





Good Topography

Site Survey & Investigation

Some of the other major factors that are to be consideredare

• Atmospheric effect on Solar Radiation

• Daily and Seasonal Temperature Variations

• Site proximity to natural disaster prone areas

• Site climatic conditions with regards to wind speeds,saline atmosphere conditions etc.

• Site land topography. This will impact on the civilfoundation requirements

• Proximity for power evacuation

• Proximity to polluting industries

• Easy site access

12



Cognizance for site selection

13

Solar Resource Assessment

Step 1

Type the following link in the web browser

http://eosweb.larc.nasa.gov/cgi-bin/sse/sse.cgi ?

14

http://eosweb.larc.nasa.gov/cgi-bin/sse/sse.cgi







Step 2

Click on Meteorology and Solar Energy section. The page as detailedbelow will be displayed

15

Solar Resource AssessmentStep 3

• Click on Enter Latitude and

Longitude part of Data tables for

a particular location. The

following page will be displayed

• This is known as Login screen.

User has to enter

– E-Mail ID

– Password of his choice

– Re enter the same password

in third field

16




Step 4

After entering all the details, by clicking on Submit button, the followingscreen will appear

17


Step 5

• If the user is interested in solar

radiation assessment in Delhi, one

has to enter the following values

in the latitude and longitude

field of the screen.

Latitude : 28.38 N

Longitude : 77.12 E

After entering the values, the

screen will be as shown.

Then, Click on Submit

18




Step 6

Choose parameters as per your requirement

19


Step 7

Clicking on Submit provides the following output

20




The following stage of evaluation is to carried out while designing

/ verifying• Weather data NASA / METEORNOM

• Simulation programme

• Choice of system components (Max. efficiency components)

• Software to be used

- PVsyst

- RETScreen

- System Advisory Model

- TRANSYS

- PYSOL

• Simulation

• Analysis of yield

21


Case Study

To design a 5MWp solar PV grid-connected power plant at a

designated location in Bangalore

Design Inputs

• Site Details

– Bangalore , Latitude-13 0 Longitude- 77 0

• DC Plate Rating

– 5 MWp

• Technology

– Thin Film Technology

• Inverter

– Central Inverter

• Grid Voltage for Power Evacuation

– 33 kV

22




Option : Project design, System : Grid-Connected

23


Click on Project

24




Select ‘New Project’ enter the relevant data and then click ‘Site and

Meteo’

25


Enter relevant data

26




Click ‘Open’ to enter the Location parameters of the site

27


Geographical Parameters

Enter Latitude, Longitude, Altitude etc. and go to ‘Monthly meteo’

tab to see the irradiation data

28




Irradiation Data

Irradiation unit can be chosen as required and click ‘OK’.

29


Situation & Meteo

Situation and Meteo window appears click ‘Next’

30




Operating temperature

Depending on site choose summer operating temperature forVmpp Min design (the default is 60⁰ C) and click ‘OK’

31

Energy Yield EstimationOrientation

click on ‘Orientation’

32




Tilt

• Click ‘Unlimited Sheds’ enter the ‘Plane Tilt’, ‘Pitch’, ‘Coll. band

width’ and select the ‘Electrical Effect’ and click ‘Show Optimisation’

33


Shading loss

Shading Loss is displayed in this window. Close this window and

‘OK’

34




System

Click ‘System’

35


Module and Inverter selection

‘Enter Planned Power’, ‘Select PV module’, ‘Select the inverter’

36




String definition

Select ‘Mod. In series’, enter ‘No. strings’ and click ‘Detailed Losses’

37


PV Filed losses (Thermal)

Enter ‘NOCT coefficient’ as given in Module datasheet and go to

‘Ohmic Losses’ tab

38



2


PV Field - losses (Ohmic)

Enter ‘DC circuit loss fraction at STC’, choose ‘Significant length’and enter ‘Loss fraction’, ‘External transformer’ and enter the ‘Iron

loss’ & Inductive loss’ also enter the Vac and go to ‘Module Quality -

Mismatch’ tab.

39

Energy Yield EstimationPV Field – losses (Module Mismatch)

Enter the ‘Mismatch Losses’ and go to ‘Soiling Loss’ tab

40



2


PV Field - Losses (Soiling)

Select the ‘Soiling Loss’ of 3% and go to ‘IAM Losses’ tab

41

Energy Yield EstimationIAM Losses

Typical bo value is 0.03 for TF and 0.05 for crystalline and click ‘OK’

42



2


Click OK

43

Energy Yield EstimationSimulation

Click ‘Simulation’

44



2


Simulation Parameters

Click ‘Simulation’

45

Energy Yield EstimationSimulation Progress

Click ’OK’

46



2


Simulation Results

Click ‘Report’

47

Energy Yield EstimationPVSYST Design Report

48



2


PVSYST Design Report

49


PVSYST Design Report

50






PHOTOVOLTA IC (PV) – INSTALLER

GUIDE

Objective

• Verify System Design

• Managing the project

• Installing electrical components

• Installing Mechanical components

• Completing system Installations

• Conduction system maintenance & Troubleshooting Activity.

2



Introduction

Balance of system (BOS) component include all mechanical of electricalequipment and hardware used to assemble and integrate the major

components in a PV system

Example of BOS components include:

3

Types of systems

4



Verify system Design

• Determine Clients Need

5

6



Review Site Survey• Obtaining the necess ary information during a site survey helps plan and

execute PV installations in a timely and cost effective manner.

7

Tools Used During Site Survey

8



Array Location

9

1. Enough Area toget maximized

energy

2. Is itshaded?

3.Is the structure

strong enough?

5. How far thearray will be

mounted from

otherequipments?

4. How will thearray be mounted?

Array Location

10

How will the array

be installed &

maintained?

Will the array be subjectedto damage or accessible to

unqualified person?

Are there any local codes or

wind load concerns for areas

of PV installation?

Are there addi tional

safety, install ation or

maintenance concern?



Array Area

For multiple rows of tilted racks or for tracker installation additionalspacing is required between each array mounting structure to prevent the

row to row shading. Additional area is required for installation of other equipments. Usually

for 1 KW dc crystalline power plant we need approximately 80 to 100 sf of

surface area.

As a thumb rule we can say that for 1 KW power plant approximately 16square meter area is required.

11

Perform a shading analysis• PV array should be unshaded at least 6 hours during the middle of the day to

produce the maximum energy possible.

• Ideally there should be no shadow between 9 a.m. and 3 p.m. solar time over

the year, since the majority of solar radiation and peak system output occur

during this period.

12



Sun Path finder

13

Array mounting method.• PV array can be mounted on the ground, rooftops and other structures that

provide adequate protection, support and solar access. The site conditionsand Results of the s ite survey usually dis tance the best mounting system

location and approach to us e.

14



Array mounting systems

15

Building integrated

Mounting System

Roof Structure and conditions

Key points:

1. Check out the roof’s load bearing capacity and its underlying

structures so that it can bear the additional load.

2. A civil engineer need to calculate the load with respect to local code

compliance. We can also refer to standard ASCE 7 – minimum loadsfor buildings and other structures.

3. A standard roof mounting structure weighs between 3 and 5 poundsper square feet which is fine for most roofs designed to recentstandards.

4. A span table can help to quantify the load bearing capabilities of rooftrusses or beams. The website for this is www.solarabcs.org.

16

http://www.solarabcs.org/

http://www.solarabcs.org/



Roof Structure and conditions

1. Wind loads are the primary concern for roof top mounting systems. For

hurr icane prone regions the design wind load can be as high as 150 mph

which can exceed the actual wind load of 50 PSF and more in some cornersof roof or structure. A structure engineer is required for the approval of the

structures with respect to the wind load design of the array.

2. Before deciding the PV array mounting system verify with the mountingsystem supplier that the hardware is appropriate for the given application.

3. For comm ercial roof mounting system we can use the ballasted mountingsystem. This is s ignificantly heavier than mounting system designed fordirect structural attachments. But this system needs special load calculation.

The main advantage is the possibility of roof leaks is greatly diminished.

17

BOS Location 1. Selection of appropriate location for all the BOS.

2. The BOS have to e w eather resistant. They may need to be installed in the

weather resistant enclosures. For this w e can refer to article 110 from NEC.

3. Avoid installing electrical equipments in locations exposed to hightemperature and direct sunlight and provide adequate ventilation andcooling for heat generating equipments like inverters, generators, chargecontrollers etc. It is always better to have proper IP rating for these

equipments to avoid damage from rain, dust, chemical and otherenvironmental factors.

4. Battery location should be protected from extreme cold area because this will

reduce the available capacity. They should be installed as pe r NEC 480.

5. Protection should be taken to prevent the attack from insects, rodents and

other debris.

18



Confirm System Sizing : Size module mounting Area

• If site is selected for array location, it is necessary to determinewhether the place is enough for the proposed number of PV modules.

• For Areas with NON-rectangular shapes, determine the amount ofusable area can be challenged.

• Access to the modules must be provided in case systemmaintenance is needed.

• Smaller array surface area are required to generate the same amountof power with higher efficiency modules.

19

Confirm System Sizing : Arrange Modules in mounting area

• Sitting the PV array in the available Mounting area can have a large impact on

the performance of a PV array.

• Each set of modules in a series string must be oriented in the same direction if

the string is to produce its full output potential.

• Is it possible to split a string between two roof faces, provided the modules

keep the exact same orientation

EXAMPLE :

20





Confirm System Sizing :Review Energy Storage Systems

23

• The battery state of charge is related to the concentration of sulfuric acidconcentration. This is measured by specific gravity.

• Specific gravity is the ratio of the density of a solution to the density ofwater.

• A fully charged lead acid cell has a typical specific gravity between 1.26and 1.28 at room temperature.

• The specific gravity may be increased for lead-acid battery used in cold

weather applications. Conversely, the specific gravity can be decreasedfor application in warm climate.

• In very cold climate the battery should be protected from freezing bylimiting minimum temperature in a suitable enclosure or by limiting the

Depth of Discharge.


Depending on the application or site requirement many factors are consideredto select the battery and for system design as follows:

• Electrical properties: voltage, capacity, charge/discharge rates

• Performance: cycle l ife vs. DOD, system autonom y

• Physical properties: s ize and weight

• Maintenance requirements: flooded or VRLA

• Installation: Location, structural requirements, environmental conditions

• Safety and auxiliary systems: racks, trays, fire protection, electrical BOS

• Costs, warranty and availability.

24



Confirm System Sizing: Review Energy Storage System

25

Electrical Properties:

voltage, capacity,

charge/discharge rates

Performance:

cycle li fe Vs. DOD,

system autonomy

Physical properties:

Size and weight

Maintenance

requirements:

Flooded or VRLA

Installation: location, structuralrequirements, environmental conditions

Safety and auxil iary systems: racks, trays,fire protection, electrical BOS

Costs,

w arrantyand

availability


• Racks and trays are used to support battery systems and provide electrolytecontainment

• Racks can be made from metal, Fiberglass or other structural non conductivematerial.

• Metal racks must be painted.

• Due to potential for ground faults, metals or other conductive battery tracks arenot allow ed for open Vent f looded lead ac id batteries more than 48 Voltsnominal.

• If batteries are connected in series to produce more than 48 V, then the

batteries must be connected in a manner that allow s the series strings ofbatteries to be separated into s trings of 48 V or less for maintenance.

• Overcurrent protection device or other such protective equipment's should beinstalled on the battery side to protect battery f rom fault currents.

26



Charge controller operations• A battery charge controller limits the Voltage and current delivered to battery

from a charging source to regulate state-of-charge.

•

A CC is required in most PV systems that use battery storage.• PV array must not be capable of generating voltage or current that will

exceed the CC input voltage & current

• The CC rated continuous current mus t be 125% of the PV array Shot circuit

O/p current.

• The CC m aximum i/p voltage should be greater than the m aximum systemvoltage

27

Charge controller operations : Set points Set Point:

Set points are the battery voltage levels at which a charge controller performs

regulation or control functions. The [proper regulation set points are critical foroptimal battery charging.

28

1. Regulation Voltage (VR) is the

maximum v oltage set point the controller

allows the battery to reach bef ore the array

current is disconnected or limited.

2. The array Reconnect Voltage(ARV) – f or interrupting ty pe controllers, is

the v oltage set point at which the array is

reconnected to charge the battery

3. Low Voltage Disconnect (LVD) – defines the maximum battery depth of

discharge at the given discharge rate.

4. Load Reconnect Voltage(LRV)- the set point where load are

reconnected to battery. A higher LRV

allows a battery to receiv e more charge

before loads are reconnected t o the

battery.

For a ty pical lead acid cell a LVD set point of 1.85

VPC to 1.91 VPC corresponds to a DOD of 70 to

80% at C/20 discharge rates or lower.

Load

Battery Bank

InverterCharge

controller



Charge controller operations : PWM VS Advance CC

:

29

Charge controller operations

• The temperature Compensation is a feature of CC that automatically adjusts

charge regulation voltage for battery temperature changes.

• The sensors can be internal or may be fixed to batteries.

• Temperature compensation is recommended for all types of sealed batteries,

which are more sensitive to overcharging than flooded type.

• Temperature compensation Helps to ful ly charge a battery during colder

conditions, and helps protect i t from Overcharge and Over discharge.

• For larger systems, the O/p of multiple CC may be connected in paralle l and

used to charge a single battery bank.

•

A diversionary CC diverts excess PV array power to Auxil iary loads whenprimary battery is fully charges.

30



Maximum power point tracking (MPPT)

• A MPPT Charge controller operates PV arrays at Maximum power

under all operating conditions independent of battery voltage.

• MPPT can improve array utilization and allow non-stnadard and higherarray operating voltages, requiring smaller conductors and fewersource circuit to charge lower voltage battery bank.

• Normally the O/p current of a MPPT will be less than or equal to the I/pCurrent.

• If a MPPT CCU is used it is important to consult the Manufacturer’sspec to determine the Maximum O/p load.

31

Series connections

32



Parallel connections

33

PV Inverter Stand Alone inverter: operates from battery and supply power independent of the

ele ctrical utility system. They may also include battery charger to operate froman independent AC source such as generator.

Bi-modal inverter: battery based interactive inverter acts as diversionary charge

controllers by producing AC power o/p to regulate PV array battery charging andsends excess power to the grid when energized.

.

34



PV Inverter Utility-interactive or grid connected inverter: operates from PV arrays an supply

pow er in parallel w ith an electrical production and distribution network.

Types:

1. Module level inverter: They include AC modules and micro inverters. They are

sm all and rated for 200 to 300W maximum. Advantages of these inverters are,they include individual module MPPT and better energy harvest from partially

shaded and multi directional arrays. More safer than string inverters as themaximum dc voltage on array is for a single module (35 -60V).

2. String Inverter: small inverters in the 1 KW to 12 KW s ize range, intended for

residential and small commercial applications. Generally single phase and

limited to 1 to 6 parallel connected source circuits.

35

Different types of Grid interactive inverters.

36

Central inverter – 30 kW to 1 MW



Specification of inverters

37

Inverter Standards

38



2

Review Wiring and conduit size calculations

Determine circuit current :

PV Power Source Maximum circuit current :

Inverter output circuit current :

39

Calculate required ampacity of the conductor (Wire)

The required am pacity of conductors is based on :

• Maximum Circuit current

• Size of overcurrent protection device

• Ambient temperature of the conductor

• Type of conductor and insulation

• The conduit fill of the conductor

40



2

41

42



2

43

44



2

Calculate Voltage Drop

45

46

Link to calculate the voltage drop:

http://www.csgnetwork.com/voltagedropcalc.html





2

47

Personal protective equipment's

48



2

PV string cables, PV array cables and PV DC main cables shall beselected and erected so as to m inimize the risk of earth faults and short-circuits.

Wire Management: Array conductors are neatly and profess ionally held inplace

Wiring systems shall withstand the expected external influences such aswind, ice formation, temperature and solar radiation.

49

Install Wiring systems

Install Wiring systems Protection by use of class II or equivalent

insulation should preferably be adopted on theDC side.

Common Installation Mistakes with WireManagement:

1. Not enough supports to properly control cable.

2. Conductors touching roof or other abrasivesurfaces exposing them to physical damage.

3. Conductors not supported within 12 inches ofboxes or fittings.

4. Not supporting raceways at proper intervals .5. Multiple cables entering a single conductor cable

gland (aka cord grip)

5. Pulling cable ties too tight or leaving them tooloose.

6. Bending conductors too close to connectors.7. Bending cable tighter than allowable bending

radius.8. Plug connectors on non--‐locking connectors not

fully engaged50



2

Install Grounding system

51

Utility Interconnection

52



2

Installing Mechanical Components

53

CIVIL CONSTRUCTIONS

54



2

Install PV modules

55

Selection of Modules

56



2

Install PV modules

57

Commission of systems

58



3

Visual Inspection

59

Test the System

60



3

THANK YOU.




IEC 62446: Grid Connected Photo Voltaic Systems –

Minimum Requirements for System Documentation,

Commissioning Tests and Inspection

Learning Objective

.

2

commissioning tests

inspection criteriadocumentation

To verify the safeinstallation and correct

operation of grid

connected solar Powerplants



Content

Clause 4:System documentation requirements

Clause 4.2: System Data

Clause 4.3:Wiring diagram

Clause 4.4: Datasheets

Clause 4.5:Mechanical design information

Clause 4.6:Operation and maintenance information

Clause 4.7:Test results and commissioning data

Clause 5 :Verification

Clause 5.2:Inspection

Clause 5.2: Testing

Clause 5.2: Verification reports

3


Clause 4: System

documentation requirements



5

4.2 System data - Basic system information

6

Project identification reference (where applicable).

Rated system power (kW DC or kVA AC).

PV modules and inverters - manufacturer, model and quantity.Installation date.

Commissioning date.

Customer name.

Site address.

PV m odules and inverters - manufacturer, model and quantity.



4.2.2 System designer information

Information shall be provided for all bodies responsible for the design of thesystem. Where more than one company has responsibility for the des ign of

the system, information's together with a description of their role in theproject.

7

System designer,company.

System designer , contactperson.

System designer,postal address,

telephonenumber and e-mail address.

4.2.3 System installer informationInformation shal l be provided for all bodies responsible for the installation of

the system. Where more than one com pany has responsibility for theinstallation of the system, information should be provided for all companiestogether with a description of their role in the project.

8

System installer,company

System installer, contactperson.

System installer,postal address,

telephonenumber and e-

mail address.



4.3 Wiring diagram

9

Array - generalspecifications

PV string

information

Arrayelectrical

details

Earthing andovervoltage

protection

a) Module type(s)

b) Total number of

modules

c) Number of

strings

d) Modules perstring

a) String cable

specifications –

size and type.

b) String over-

current protective

device

specifications

c) Blocking diode

type (if relevant).

a) Array main

cable

specifications –

size and type.

b) Array junction

box locations

c) DC isolatortype, location

and rating

d) Array over-

currentprotective

devices – type,

location and

rating (voltage

/ current).

a) Details of allearth / bonding

conductors

b) Details of any

connections to

an existingLightning

Protection

System (LPS).

c) Details of anysurge

protectiondevice installed

(both on AC

and DC lines)to include

location, type

and rating.

AC system

a) AC isolator

location, type

and rating.

b) AC

overcurrent

protective

device

location, typeand rating.

c) Residualcurrent device

location, typeand rating

(where fitted).

10



4.4 Datasheets

Datasheets shall be provided for the following system components

NOTE The provision of datasheets for other significant system

components should also be considered.

11

Module datasheet for all types ofmodules used in the system - tothe requirements of IEC 61730-1.

Inverter datasheet for all types of

inverters used in the system.

4.5 Mechanical design information A data sheet for the array mounting system shall be provided.

12



4.6 Operation and maintenance information

Operation and maintenance information shall be provided and shall

include, as a minimum, the following items:

13

Procedures

f or verif ying

correct

system

operation.

A check list

of what to

do in case

of a

system

f ailure.

Emergency

shutdown /

isolation

procedures

Maintenanceand cleaning

recommendat

ions (if any).

Considerations

for any future

building works

related to the PVarray (e.g. roof

works).

Warranty

documentation for

PV modules and

inverters - to includestarting date of

warranty and period

of warranty.

Warranty

Documentation on any

applicable

workmanship orweather-tightness

warranties.


Clause 5 : Verification



5.3 Inspection (Requirements)

PV array design and installation

PV system - protection against overvoltage / electricshock

PV system - AC circuit special considerations

PV system - labelling and identification

PV system - general installation (mechanical)

15


PV array design and

installation.



Stand Alone SPV power Plant

17

Grid Connected SPV power plant

18



Field Inspection Checklist for Array:

1. Number of PV modules and model number matches plans and specsheets

2. with the module model number and quantity of modules confirmed, the

physical layout of the array should match the supplied s ite plan.

Common Installation Mistakes with Array Modules and Configurations:

1. Changing the array wiring layout without changing the subm itted electricaldiagram.

2. Changing the module type or manufacturer as a result of supply iss ues.

3. Exceeding the inverter or module voltage due to improper array design.

4. Putting too few modules in series for proper operation of the inverter during

high summer array temperatures .

19

Ratings for DC Components

• DC components rated for current and voltage maxima (Voc stc

corrected for local temperature range and module type; current at

Isc @ stc × 1.25

Note:

1) Overload protection may be omitted to PV string and PV array

cables when the continuous current-carrying capacity of the cable

is equal to or greater than 1,25 times ISC STC at any location.

2) Overload protection may be omitted to the PV main cable if thecontinuous current-carrying capacity is equal to or greater than

1,25 times ISC STC of the PV generator.

20







DC switch disconnector

In every PV installation it is

necessary to isolate thephotovoltaic panel from therest of the system.

DC Isolators must have ahigher performance than thetraditional AC Isolatorsbecause breaking directcurrent is more difficult thanbreaking alternating current.

DC switch disconnectorshould be fitted to the DC sideof the inverter.

25

415V, 63A, 3pole AC MCB

Example to calculate the disconnect devices

• Example of PV sizing of disconnect switches.

Determine the minimum size in terms of Voltage and current of the disconnect based onfollow ing informations:

Maximum input operating range : 300 -480 V dc

Maximum input voltage (Voc) : 600V

Maximum rated input current : 800A (DC)

Maximum input Isc rating : 1200 A (DC)

Maximum rated output current : 300 A (AC)

26



Example to calculate the disconnect devices

Solution :

• PV Disconnect

Maximum continuous input current = maximum input short circuit current rating* 125%

= 1200A * 125% = 1500A (DC)

Maximum input Voltage (Voc) = 600 V (DC)

The PV dis connect switch must be rated for minimum of 1500A (dc) @ 600

V (dc). PV disconnect devices for 1000Vdc shall be evaluated under UL98B.

27

Blocking diodes.

If blocking diodes are used,

their reverse voltage should berated for 2 × Voc STC of the

PV string.

The blocking diodes shall be

connected in series with the

PV strings.

28





Type B residual current device.

Residual current device for which tripping is

ensured:

for residual sinusoidal alternating currents up to 1000

Hz.

for residual alternating currents superimposed on a

smooth direct current of 0.4 times the rated residual

current.

for residual direct currents which may result from

rectifying circuits. for residual smooth direct currents.

31

Protection against electromagneticinterference.

The area of all wiring loops shall be as small as

possible, to minimize voltages induced by lightning.

32



Lightning.

In the event of a lightning strike or

surge the surge arrestor conductsthe charge bleeding it out of the

circuit to ground.

33

Each LIGHTNING ARRESTER shallbe earthed through suitable size earthbus bar with earth pits.


PV system - AC circuit

special considerations.



AC circuit special considerations.

Means of isolating the inverter should be provided

on the AC side.

Inverter protection settings should be programmedto local regulations.

36

AC circuit special considerations.

In the selection and erection of devices for isolationand switching to be installed between the PVinstallation and the public supply, the public supplyshould be considered as the source and the PVinstallation shall be considered the load.

To allow maintenance of the PV inverter, means ofisolating the PV inverter from the DC side and the

AC side shall be provided.

37




labelling and identification

Labelling.

All circuits, protective devices,switches and terminals aresuitably labelled.

All DC junction boxes (PVgenerator and PV array boxes)

carry a warning label indicatingthat active parts inside theboxes are fed from a PV arrayand may still be live afterisolation from the PV inverterand public supply.

39



2

Labelling.

Main AC isolator are clearlylabelled.

Dual supply warning labels arefitted at point ofinterconnection.

Single line wiring diagram isdisplayed on site.

Inverter protection settings andinstaller details are displayedon site.

Emergency shutdownprocedures are displayed onsite.

40

PV system - general installation (mechanical)

Ventilation has to be

provided behind arrayto prevent overheating /

fire risk.

41



2

General installation (mechanical)

rray frame and materialas to be corrosionsistant.

rray frame has to beorrectly fixed and stablend roof fixings should beeatherproof.

42

Cable entry has to be weatherproof.

43

Cables through roofing shall be

contained in roof-entry boxes,

which also shall form a

waterproof seal to avoid

leakage.

All Cable entry shall be thoroughly

sealed and made waterproof with

UV-resistant silicone sealant or

equivalent.



2


Testing : PV array

Parameters of testing

1. polarity test

2. string open circuit voltage test

3. string short circuit current test

4. functional tests

5. insulation resistance of the DC circuits

6. continuity of protective earthing and/or equipotential bondingconductors

45



2

polarity test

The polarity of all DC cables shall be verified using suitable test

apparatus. Once polarity is confirmed, cables shall be checked to

ensure they are correctly identified and correctly connected into

system devices such as switching devices or inverters.

46

Array Parameters – Voc & Isc

PV string - open circuit voltage measurement

• The open circuit voltage of each PV s tring should be measured usingsuitable measuring apparatus. This s hould be done before closing any

switches or ins talling string over-current protective devices (where fitted).

• Measured values should be com pared with the expected value. Comparisonto expected values is intended as a check for correct installation, not as a

measure of module or array performance.

• For systems with multiple identical strings and where there is stable

irradiance conditions, voltages between strings shall be compared. These

values s hould be the same (typically within 5 % for s table irradianceconditions). For non stable irradiance conditions, the following methods can

be adopted:

• testing may be delayed

• tests can be done using multiple meters, with one meter on a

reference string

• an irradiance meter reading may be used to adjus t the currentreadings.

47



2

PV string - current measurement

• Like the open circuit voltage measurements the purpose of a PV

string current measurement test is to verify that there are no major

faults within the PV array wiring. These tests are not to be taken as

a measure of module / array performance.

• Two tests methods are possible and both will provide information on

string performance. Where possible the short circuit test is preferred

as it will exclude any influence from the inverters.

a) PV string – short circuit test

b) PV string – operational test

48

PV string – short circuit test procedure• Ensure that all PV strings are isolated from each other and that all

switching devices and disconnecting means are open.

• A temporary short circuit shall be introduced into the string under

test. This can be achieved by either:

a) A short circuit cable temporarily connected into a load break

switching device already present in the string circuit.

b) The use of a “short circuit switch test box” – a load break rated

device that can be temporarily introduced into the circuit to create a

switched short circuit.

In either case the switching device and short circuit conductor shall be

rated greater than the potential short circuit current and open circuit

voltage.

The short circuit current can then be measured using either a clip on

ammeter or by an in-line ammeter

49



2

PV string – operational test procedure

• With the system switched on and in normal operation mode

(inverters maximum power point tracking) the current from each PV

string should be measured using a suitable clip on ammeter placedaround the string cable.

• Measured values should be compared with the expected value. For

systems with multiple identical strings and where there are stable

irradiance conditions, measurements of currents in individual strings

shall be compared. These values should be the same (typically

within 5 % for stable irradiance conditions).

• For non-stable irradiance conditions, the following methods can be

adopted:

a) testing may be delayed

b) tests can be done using multiple meters, with one meter on areference string

c) an irradiance meter reading may be used to adjust the current

readings.

50

Array insulation resistance - PrecautionsPV array DC circuits are live during daylight and, unlike a conventional AC

circuit, cannot be isolated before performing this test.

Performing this test presents a potential electric shock hazard, it is important to

fully unders tand the procedure before starting any work. It is recomm endedthat the following bas ic safety measures are followed:

• Limit the access to the working area.

• Do not touch and take measures to prevent any other persons to touch anymetallic surface with any part of your body when performing the insulation

test.

• Do not touch and take measures to prevent any other persons from touching

the back of the module/laminate or the module/laminate terminals with anypart of your body when performing the insulation test.

• Whenever the insulation test device is energized there is voltage on thetesting area. The equipment is to have automatic auto-discharge capability.

51



2

PV array insulation resistance test - test

methodThe test should be repeated for each PV array as a minimum. It is also

possible to test individual strings if required. Two test methods arepossible:

TEST METHOD 1 - Test between array negative and earth followed by

a test between array Positive and Earth.

TEST METHOD 2 - Test between earth and short circuited array

positive and negative.

52

PV array insulation resistance test - testmethod• Where the structure/frame is bonded to earth, the earth connection

may be to any suitable earth connection or to the array frame (where

the array frame is utilized, ensure a good contact and that there is

continuity over the whole metallic frame).

• For systems where the array frame is not bonded to earth (e.g.

where there is a class II installation) a commissioning engineer may

choose to do two tests: a) between array cables and earth and an

additional test b) between array cables and frame.

• For arrays that have no accessible conductive parts (e.g. PV roof

tiles) the test shall be between array cables and the building earth.

53



2

PV array insulation resistance test - test

method• Before commencing with the test: limit access to non-authorized personnel;

isolate the PV array from the inverter (typically at the array switchdisconnector); and disconnect any piece of equipment that could have an

impact on the insulation measurement (i.e. overvoltage protection) in the junction or combiner boxes.

• Where a s hort circuit switch box is being used to test to method 2, the arraycables should be securely connected into the short circuit device before theshort circuit switch is activated.

• The ins ulation resistance test device shall be connected between earth andthe array cable(s) as appropriate to the test method adopted. Test leadsshould be made secure before carrying out the test.

• Follow the insulation resistance test device instructions to ensure the testvoltage is according to Table 1 and readings in MΩ. The insulation

resis tance, measured with the test voltage indicated in Table 1, issatisfactory if each circuit has an insulation resistance not less than theappropriate value given in Table 1.

• Ensure the system is de-energized before removing test cables or touchingany conductive parts.

54

PV array insulation resistance test - testmethod

55



2

5.4.2 Continuity of protective earthing and/or

equipotential bonding conductors

Apply current = 2.5 X fuse rating

Fuse rating = 1.35 X Isc

For example if the string have current of 8A, the fuse rating w ill be 10.8A =15A

Apply current = 2.5 X 15 = 37.5 A

56

PV PV PV PV PV

PowerSupply

5.4.6 Functional tests

The following functional tests shall be performed:

a) Switchgear and other control apparatus shall be tested to ensure correctoperation and that they are properly mounted and connected.

b) All inverters forming part of the PV system shall be tested to ensure correctoperation. The test procedure should be the procedure defined by theinverter manufacturer.

c) A loss of mains test shall be performed: With the system operating, the main

AC isolator shall be opened – it should be observed (e.g. on a displaymeter) that the PV system immediately ceases to generate. Following this,the AC isolator should be re-closed and it should be observed that the

system reverts to normal operation.

57



2

THANK YOU.




Shadow affect on PV panels.


INTRODUCTION

The choice of a proper location is the first and the very essential

step in solar system design procedure. The modules have to befixed w ith proper tilt angle and distance to prevent Shadow on

the module for efficient operation.



Sun

• The sun is a gaseous body composed mostly

of hydrogen.

• Gravity causes intense pressure and heat at

the core initiating nuclear fusing reactions.

• Even when planet Earth is 93 m illion m iles away, we still receive

an amazing quantity of usable energy from the sun.

3

Solar energy in India.

Today, more than 40% of the Indian population, or

approximately 1,25,000 villages, have no access to reliable electricity.

If 1.25% of Indian Land is used to harness Solar energy, It would

yield 8 million Mega watt.

It is equivalent to 5909 mtoe(million tons of oil equivalent) per year.

4



Solar Radiation Spectrum

5

Solar Radiation

• Solar irradiance is the intensity of solar power, usually expressed in

Watts per square meter [W/m^2]

• Since the proportion of input/output holds pretty much linearly for

any given PV efficiency, we can very easily evaluate a system

performance by measuring irradiance and the PV module output.

• Solar spectral distribution is important to understanding how the PV

modules respond to it.

• Most Silicon based PV devices respond only to visible and the near

infrared portions of the spectrum.

• Thin film modules generally have a narrower response range.

6



Solar Intensity on Planets.

7

Solar Radiation

www.cabrillo.edu/.../Chapter%202%20 Solar %20 Radiation





Latitude

North Pole

South Pole

Lines of latitude arenumbered from 0° at theequator to 90° at the North

Pole.

Lines oflatitude arenumbered from 0°at the equator to90° at the South

Pole.

][

9080

70

60

50

40

20

30

10

90

80

70

60

50

40

20

10

30

Longitude

The prime meridian is the vertical line that marks the zero degree longitudemeasurement on the globe of Earth.

Lines of longitude are numbered east from the Prime Meridian to the 180°

line and west from the Prime Meridian to the 180° line.

PRIME MERIDIAN

W e s t L on gi t u d e

E a s t L on gi t u d e

180°N

EW

S

North Pole



True South

In the Northern Hemisphere,

stationary PV arrays are orientedsouth to maximize PV output. But

using your compass to find south

will only give you an indication of

magnetic south, not True South.

.

13

The difference in the orientation is called as magnetic

declination.

True North

In the Southern Hemisphere,stationary PV arrays are orientednorth to maximize PV output. But

using your com pass to find northwill only give you an indication of

magnetic north, not True North.

The follow ing link can be used to f ind the magnetic declination at any place.

http://magnetic-declination.com/

14

Usually the magnetic declination should be either subtracted oradded to your magnetic compass reading to find True North orTrue south. The declination is based on your latitude and

longitude.



Altitude-Azimuth coordinate system

Based on what an observer sees in the sky.Zenith = point directly above the observer (90o)

Nadir = point directly below the observer (-90o

) – can’t be seen Horizon = plane (0o)

Altitude = angle above the horizon to an object (star, sun, etc)

(range = 0o to 90o)

Note: lines of azimuthconverge at zenith

Zenith angle.• Zenith is the point in the sky directly overhead a particular location –asthe Zenith angleӨz increas es, the sun approaches the horizon.



Solar Radiation

Tilt angle is the vertical angle between the horizontal and thearray surface

• Array orientation is defined by two angles:

www.cabrillo.edu/.../Chapter%202%20 Solar %20 Radiation

Altitude and Azimuth angle.

Solar Altitude Angle is the vertical angle between the sun and the

horizon –added to the Zenith angle is equal to 90º. Azimuth Angle is the horizontal angle between a reference direction.In the solar industry we call south 180º and this angle will range between

90º (east) and 270º (west).



Array Azimuth Angle.

Array Azimuth Angle is the horizontal angle between a

reference direction – typically south - and the direction anarray surface faces.

Solar Declination.

• Solar Declination is the angle between the equatorial plane and the ecliptic plane

• The solar declination angle varies with the season of the year, and rangesbetween –23.5º and +23.5º



Solstices.

Summer Solstice is at

maximum solar declination

(+23.5º) and occurs aroundJune 21st –Sun is at Zenith at

solar noon at locations 23.5º N

latitude.

Winter Solstice is at minimum

solar declination (-23.5º) and

occurs around December 21st

At any location in the Northern

Hemisphere, the sun is 47º

lower in the sky at noon onwinter solstice than on the

summer solstice – Days are

significantly shorter than nights.

Sun path

Sun path refers to the apparent significant seasonal-and-hourly

positional changes of the sun as the Earth rotates, and orbits

around the sun.

Sun path helps us to find,

Azimuth angle and Altitude angleFor particular place at specific

Time of the day.

22



Steps to find Azimuth angle and Altitude angle.

Step 1: Select the sun path diagram for the site latitude (or nearest latitude).

For Bangalore 12˚58’ North latitude may be selected. Step 2: Find the date curve for December 21. Step 3: Find the hour line for 9:00 am and mark its intersection with the curve of December 21. Step 4: Lay a straight-edge from the center of the chart from the observation point) through the marked

hour point to the perimeter cir cle. Read the Azimuth Angle from the perimeter scale. For this

example (α) = 127˚. Step 5:

On he straight line, measure the distance in mil limeter between the perimeter circle and themarked point. Each mil limeter represents one degree of altitude angle. This distance will be

measured 28.5 mm. This means the altitude of the sun at 9:00 am of December 21 in Bangalore

is (θ) = 28.5˚.

23

For a certain location, for a certain day and hour, azimuth and altitudeangles may be defined by the following procedure. For this purpose the sun pathdiagram prepared for that location should be used.

Example : Define the position of the sun in Bangalore at 9:00 am of December 21.

SUN path for Bangalore.

24



Hourly Sun Path

25

Annual Sun Path

26



The main aspect to study are

• Tilt of the solar panel.

• Shadows of extern elements.

• Shadows of own elements.

27

Edge shadowing.

Shading of one region of a module

compared to another leads to

mismatch is PV modules.

28

Edge shadowing which may happen in PVfield due to dust accumulated on the tilted PVarray. This happens intensively in the bottom

edges of the panels causing another type ofreduction of the PV output.

Edge shading is also possible to

happen in field due to the shadows

cast by other PV cells and the tilt, the

orientation and the surface

temperature variation of the PV panel.





Orientation angle

• The most favorable orientation is 180º South (North

hemisphere).

• For Southern hemisphere 0º North.

• An orientation deviation below 20º (East or West) cause

negligible system losses.

31

Distance between panel rows

A basic rule would be to avoid shadows during the 6 – 8 central

hours of the day, in the day of the year with less radiation.

This implies calculating the angle of the sun (height regarding the

line of the horizon) to +/- 3 - 4 hours regarding the solar midday. This

angle will vary depending on the latitude.

The objective is to avoid that the top of the front panel projects a

shadow to the lowest part of the panel that is placed behind.

32



Distance between the panels.

D = Sin ( + Θ ) * H

Sin

(Θ ) The variable is the tilt of the panels.

(H ) The height of the panel.

(α ) is a function of the latitude of the installation and the optimal sun

elevation.

(D ) is the distance between the panels.

33

Minimum space between the panels.

Space between two rows of solar structures should be atleast twice

of the height of the solar panel structures at the highest point of tilt.This minimum space is required to avoid shadow of one row of solar

structure to fall on the row behind it.

Similarly if there is an obstacle, on the southern side of the solar

structure/modules the distance of the solar structure/module facing

the obstruction should be atleast twice the height of the obstruction.

34



Hot-Spot Heating

•Hot-spot heating occurs when there is one low current solar cell in a

string of at least several high short-circuit current solar cells.

• One shaded cell in a string reduces the current through the good

cells, causing the good cells to produce higher voltages that can

often reverse bias the bad cell.

• Power gets dissipated in the “poor” cell.

35

Hot spot effects

Local overheating, or "hot-spots", leads to destructive effects cell

or glass cracking, melting of solder or degradation of the solar cell.

36



Bypass Diodes

One by pass diode per solar cell is too expensive option. Amount mismatch depends on the degree of shading.

A partial shading will cause a lower forward bias voltage.

The maximum group size per diode, without causing damage, is

about 15 cells/bypass diode, for silicon cells.

Normally for 36 cell module 2 bypass diodes are used.

37

THANK YOU.




Grounding and Bonding in

Photovoltaic Installations

Grounding

• Grounding is the process of connecting a system, equipment or both

to the earth.

2



3

Bonding

• Bonding is the process of connecting to conductive objects together.

• Grounding and bonding means that conductive parts are connected

together and to the earth.

Grounding Faults

4





Grounding and Bonding in PV Modules

7

Grounding hardware knowhow:• Type of metal Aluminum, Copper or Stainless Steel

• Type of Screw Thread Cutting or provided with Nut

• Nut Bolt

Combination

Washer types

Grounding and Bonding in Inverters

8





Grounding of Grid connected PV System

11

Grounding of Roof Mounted PV System

12



13

Grounding and Bonding

Grounding hardware


14

Bolts and screws




15

Tightening Torque in N-m – Indicative Values

Wire size

Slotted head screw

Hexagonal

head

Slot w idth – max

1.2 mm and slot

length max 6.4

mm

Slot w idth – over

1.2 mm and slot

length over 6.4

mm

Upto 4 mm2 2.3 4.0 8.5

Recessed Allen or Square drive

Socket width across flats in mm Torque (Nm)

3.2 5.1

4.0 11.3

4.8 13.6

5.6 16.9

6.4 22.6

7.9 31.1

9.5 42.4

12.7 56.5

14.3 67.8

Electrochemical Potential

16

Copper

Tin plated Copper Stainless Steel

Aluminum




17


18

Stainless steel with Aluminum with slight trace

of chloride in the environment



Dissimilar Metal Combination –


19

Do you see any issue here ??

20



…and here ??

21

…and here ??

22



…finally here ??

23

Grounding

24

IS 3043 – Code of Practice for Earthing

Applicable for Land Based installations

• Soil Resistivity Depends upon Climate

Important considerations:

• No natural Drainage ..but no water flowing over it

• Artificial Treatment NaCl, CaCl, Na2CO3, CuCO4,

Soft Coke, Charcoal

• Shape of Electrode Plate, Rods, Pipe







Grounding

29

IS 3043 – Code of Practice for EarthingEarthing Resistance, RE

• Resistance of Metal Electrode, RM

• Resistance of earthing conductor that runs

between the main earthing bus bar and the

earthing electrode, RC

• Contact resistance between electrode and soil, RD

• RE = RM + RD + RC

Grounding

30


Earthing Resistance, RE



Grounding

31

IS 3043 – Code of Practice for EarthingEarthing Chamber (Pit) Example

Grounding

32


Material selection for Earthing electrodes

• Should exhibit galvanic potential

• Resistant to corrosion, Copper, Galvanized Mild Steel

• Damage to cables and other underground services due to

electrolytic actions between dissimilar metals

• Material compatible with other metals in vicinity



Wire Sizes

33

Wire Size (cross sectional area) depends uponfollowing:

• Admissible Maximum temperature

• Admissible Voltage drop

• Electromechanical stresses likely to occur due

to short circuits

• Other mechanical stresses to which the

conductors may be exposed• Series/ Parallel connections of PV modules

Wire Sizes

34

Grounding wire size

• For PV Module – Shall not be less than the

supply wires used in PV Module, but not lessthan 4 sq. mm

• For Installation – Not less than 10 sq mm



Fuse / Circuit Breaker rating

35

As per IEC 61730-1, the Current rating of

Series Fuse / Circuit Breaker is required to

be at least 1.25 times of Short Circuit

Current rating

THANK YOU.




Lightning Protection Systems

2

IS:2309:1989 – Protection of buildings and allied structures against

lightning

IEC 61643-1 – replaced by: IEC 61643-11

IEC 1024-1 – replaced by: EN 62305-3

IEC 62305-3 – Protection against lightning(Physical damage to

structures and life hazard)

IEC 62305-1 – Protection against lightning : General principle

2

Standard References



3

Cloud electrification – E

Field es tablished between

clouds & ground

Dow n leader approaches, EField increases to point of

initiation of upward streamers

Upward leader propagatestow ard down leader to

complete ionised path

between clouds & ground

E Fields 5-15kV/m

E Fields >200kV/m

3

Understanding the Lightning Discharge

Lightning

4

Atmospheric discharge of electricity may be accompanied by

thunder or dust storms.

Can travel at speeds of 2,20,000 km/h (1,40,000 mph)

Can reach temperatures approaching 30,000 C (54,000 F),hot enough to fuse silica sand into glass channels



Lightning Protection Systems

5

Systems designed to protect a structure from damage due tolightning strikes by intercepting such strikes and safely

passing their extremely high voltage currents to "ground".

Most lightning protection systems include a network of

lightning rods, metal conductors, and ground electrodes

designed to provide a low resistance path to ground for

potential strikes.

6

Lightning Protection System - Components

► Lightning Rod or Air Terminal

► Surge Protection Device

► Down conductor

► Other components



7

Lightning rod or Air terminations

88

Down Conductor



9

Surge Protection Device

Appliance designed to protect electrical devices from voltage spikes.

Surge arresters can be viewed as a simple switch between two lines.When voltage rises as a result of a transient, the switch operates by

diverting the energy away from the equipment.

10

Other Components





13

Example:

Note: During verification of Solar power plants lightning arresterinspection will depend upon the type of arresters used at site.

14

Rolling sphere radius, mesh size and protection angle:



15

Position Angle Method (PAM)

16

Number of Thunderstorm Days Map of India

16



LA Photos

17

18



19

20



21

22



23

Lightning Protection Devices - Video

24



THANK YOU.




Solar Photovoltaic Power Plant

- Power Evacuation System

Photovoltaic System



Power Evacuation System Design

• LT panel & associated switchgear

• Power Transformer specification

• HT panel & associated switchgear

• HT Metering

Power Evacuation Scheme

A typical MW Power Evacuation scheme

4



Power Evacuation Schematic

5

Design –

Power Evacuation

The power evacuation scheme broadly consists of

• LT panels & associated switchgear

• Power transformer of suitable rating

• HT Panel & Switchgear

• HT Metering

• DP structure to facilitate power evacuation to the HT line

6





Power Transformer (1/2)

• Power transformer rating to be suitably designed based on the solar

farm output rating• Primary Voltage same as the Output voltage of the PCU - LT winding

can be 433 volts (standard) or any other voltage to match with the

inverter output

• Secondary Voltage be equal to the Grid voltage to which power to be

evacuated - HT winding to chosen based on the inter connection

voltage – 11kV / 33 kV / 66 kV??

• KVA rating based on the number & rating of Inverters connected to

the Primary

• Should be suitable for operation with pulsed Inverter

• Impedance of max 6 %

• Minimum iron loss

• Off load taps +/- 2.5 % and +/-5 % on HV side

9

Power Transformer (2/2)

• Preferred vector grouping is DYN11 (standard)

• Transformer to have multiple LT windings if used with transformer

less inverters

• To comply with the requirements of IS : 2026

• Provide all protections like Buchholtz relay, Oil Temp ,Winding Temp,

Silica gel breather etc.

• Should specify whether you need Cable Box type termination or bus

duct termination

• To be provided with a Shield winding and grounded to the tank

• Either of the transformer windings neutral will need to be earthed

to provide a quick path for clearing of earth faults

• Neutral grounded resistors or neutral grounded transformers to be

used to facilitate the neutral point earthing

10



HT Panel & Switchgear (1/2)

• HT panel provides for interconnection from the HT winding of the

transformer to the HT transmission line

• HT panel also provides for protection, interlocking , annunciation

and tripping

• HT panel typically consists of suitably rated HT breakers, VT’s , CT’s ,

relays, meters, relevant annunciation panel etc.

• The breaker should be of appropriate voltage class depending on the

grid voltage

• The current rating should be at least 25% higher than the current

that is expected to be pumped

• Rating of the HT panel should be chosen keeping in view of the max

fault current that it should withstand depending on the substation

11

HT Panel & Switchgear (2/2)• Protective relays like O/C, E/F , IDMT, Reverse Power relay etc. to be

provided

• HT Panel can house the Energy meter to record the power exported

• In some cases separate metering kiosk including a Check meter

(utility) will have to be placed near the 2 Pole / 4 Pole Structure

• The cable from HT Panel or Metering kiosk needs to be terminated

on a 2 Pole structure or 4 Pole structure.

• GOD switch with fuse will be mounted on the structure. Rating

should match with the system requirements.

• The transmission line will be terminated on this.

• Suitable Lightning Arrestor should be provided

• Where double circuit termination is required , 4 pole structure may

be used

12



HT Metering

• HT metering panel provides for metering of the energy fed to the

grid on the HT side

• This meter is generally used by the utility authorities to quantify the

amount of energy fed into the grid.

• HT meter to conform to relevant standards.

• HT meter to have facility for communication with standard SCADA

systems

13

Transmission Line (1/2)

• The power generated at the Solar Plant has to be delivered at the

Substation (grid injection point ). This calls for an Overhead

transmission line between SPP and S/S

• The components in the overhead transmission line –

- Pole with concrete foundation - Insulators

- Conductors - Cross arms

- Stays - Earthing

- Ground Operated Device - Anti climbing device

- Danger Boards

• Each of the above items have to comply with relevant IS standards

14









Sizing of load

• Identify the loads (fan, lights etc).

•

Hour of operation.• Number of days per week

3

Load Calculations

4

LoadType

Numbers Hour ofoperation

Power(W)

kWh

fan 16 7 60 6.72

Tubelights

15 7 40 4.2

computer s

3 5 200 3

printer 2 1 300 0.60

Xeroxmachine

1 1 2000 2

AC 2 4.5 2000 18.00

AC Energy required to run these loads on230V AC

34.52 kWh



Decide on system voltage

Capacity of power plant System Voltage

Less than 1 kW 12 V

1 – 3 kW 24 V

3 – 8 kW 48 – 96 V

10 – 20 kW 120 – 240 V

5

Battery Bank Sizing

6



PV array Sizing

7

ExampleWhat will be the system required to run 4 CFL (11W) for 4 hours with 3

days of autonomy?

• Load calculation = 4 (CFL) X 11 (W) X 4 (Hours ) = 176 Wh

• System Voltage = 12 V (less than 1 kW).

Battery bank Sizing

• Ah per day required = 176 / 12 = 14.6 Ah

• Battery capacity = 3 (Autonomy) X 14.6 Ah (Ah per day) / 0.9 (batt. eff.) X0.8 (DOD)

= 60.83 Ah = 12 V, 75 Ah (As 60 Ah battery not available)

PV array sizing

•

Ah Required from PV array = 14.6 Ah (Ah required for load) / 0.8 (invertereff.) = 18.25 Ah

• Average current drawn = 18.25 (Ah from PV )/ 5 (ESSH) = 3.65 A

• This ampere can be achieved by looking the panel specification, generally75 Wp panel delivers 3.5 to 4 A current and 12 V.

• Panel in series = 3.65 (Avg. current drawn) / current of one panel = 1Number

• Panel in parallel = 12 (system voltage) / 12 (Module voltage) = 1 Number

8



Question

Q1 . What will be the system required to run 2

CFL (11W) & 1 DC fan (20 W) for 3 hours with3 days of autonomy?

Q2 What will be the system required to run 2CFL (11W) for 3 hours with 3 days of

autonomy?

9

THANK YOU.




PV System –

Operation and Maintenance.

Check list of Maintenance.

1. Module.

2. Washing the PV array.

3. Junction Box inspection.

4. Disconnect device inspection.

5. Inspection of cables.

6. Checking the operation of the inverter .7. Checking the output of string voltages and currents.

8. Spare Parts stock management

9. Documenting any deficiencies.

2



Types of maintenance.

Predictive.

Preventive.

Corrective.

3

Predictive maintenance

It tries to predict the plant performance in the

future, to prevent possible malfunctions by certain

actions.

i.e. If an element life time is supposed to be X

years, it can be programmed to be substituted the

year X-1, in order to avoid a serious failure.

4





System producing less than expected, it could

be due to:

o Shade from trees, other buildings, overhead cables, aerials.

o Mismatch of ratings between PV panel and inverter.

o Regulation problems/defective inverter.

o Mismatch of panels connected in array.

o Faults in the DC wiring.

o Defective modules.

o Defective (module) bypass diodes.

o Imbalance (voltage, current, frequency)

caused by the utility grid.

7

Panel Analysis.

8

To detect the defective panels within thearray:

a. Test both the voltage and the current foreach panel:

The voltage may be reduced if acell has any defects.

Production defects

b. The hot spots may produce a voltage reduction:

They can be detected visual ly, but a thermo graphic camera can helpto find them out.



Module Maintenance.

9

Defective cells.

Yellowing (The panel becomes

yellow)

Defective connection boxes.

Broken glass.

Delamination

Others..

They should be visually detected.

Mounting structure inseption.

Check for corrosion in the

mounting structures.

Document if any corrodedparts.

10

Repaint the corroded parts in order to prevent

further destruction of the structure.



Module wiring and ground inseption.

Check the wiring for signs of chewing by

squirrels, and look for cuts, gashes, or wornspots in the wiring’s insulation. Replace anydamaged wire runs.

Check the frame ground connections between

modules.

11

Check for any hanging wires under the modules.

Tie all the wires together with a cable ties.

12



Tighten all loose nuts and bolts, holding the

modules to the mounting rack and to themounting clips.

13

Washing the PV array.

Solar Panels are always exposed to the externalenvironment which leads to deposition of dust and debris.This causes shading in part of the array hence considerablyreducing the output of PV array.

Regular cleaning of PV array to remove the deposits on thepanels is necessary for its efficient performance.

Use a clean sponge or cloth for cleaning, to avoid scratchingon the module and no chemical should be left on the glassafter cleaning.

14



Self-Cleaning Solar Panels.

Washing the panels can be time-consuming or

require costly automation and it takes a lot of water,

a precious resource.

With the new technology, solar panels can be

automatically cleaned without water or labor.

The panels are made-up of electrodynamic screens

(EDS).

15

Junction Box.

Open the junction box

and look for any dirty,loose, creatures or

broken connections,

and correct as

necessary.

The junction boxesshould be IP 65/66/67rated.

17



Disconnect device.

18

• Periodical inspections will be done, specially in the

connections.

• If any defect is detected, the device will be

immediately replaced.

• The spare part stock is important.• Maintain a log of number of time it tripped.

Preventive:

Cable

To check the connections

between the different

equipments.

To check those parts where thecable cover can be damaged.

Check high losses/voltage drop

in cables. Check the

calculations, possibly replace

with larger cables.

19

Preventive



Preventive maintenance.

It is necessary to define the maintenance tasks and their

periodicity and then create a record of preventive

maintenance on every element, with the date of

accomplishment.

20

Example: Preventive maintenance calendar 20XX

Task Periodicity Date

Checking the cable state Yearly

Retightening of theelectrical connections

Yearly

String Inverters compared to Central Inverters.

Reliability and Longer Life.

Productivity.

Ease of Installation.

Flexibility.

Space and Heat of Inverters. Higher Power Inverters have to be used.

21




Disadvantages of String inverters

compared to Central Inverters.

Cost.

String inverters typically costs twice that of Central

Inverter.

This is the biggest disadvantage of string inverter

compared to Central inverters.

23



Placement of String inverters

String inverters areplace on the rackbelow the modules.

This is said to causeproblems as it isplaced on the hottestpart of the solarsystem and could lead

to problems in case ofhigh insolation areas.

24

Not useful in utility solar power plants.

Solar Power Plants of more than 1 MW in size have not

used string inverters.

As string inverters are more useful in power plants of

smaller size where maximum power is needed and

where there are problems of shading, debris etc.

25



Inverter Output Performances.

1. Output Voltage.

2. Output Current.

3. Output Power.

4. Output Power Factor.

5. Efficiency.

6. DC injection Current.

7. Total Harmonic Distortion (THD).

8. Current Harmonic Test.

26

Inverter overheating due to clogged vents, badventilation.

Clean inverter.

Relocate inverter.

Improve room ventilation.

27



No DC voltage at the inverter input.

• Too dark, not enough light. Come back at a bettertime when there is enough sunlight.

• Main DC disconnect/isolator in open position?Defective disconnect/isolator ?

• Check voltage at disconnect/isolator input.

• String fuses blown(lightning strike).

• Excess voltage suppressor has short-circuited thearray to earth. Check excess voltage suppressor.

28

Fault/possible cause/solution.

Inverter indicates DC input voltage during theday but nothing is being put onto the grid.

Blown fuses, activated circuit breakers and ground fault interrupts onthe AC side between inverter and grid, The main utility fuse, Checkthese.

The inverter has detected a fault in the array and shut down. Checkany fault indicators. Test strings individually in the PV arraycombiner box.

Possibly isolate the string which is causing the inverter to shut downby disconnecting one string at a time until string with fault isidentified.

The inverter has detected a grid fault or grid operating outsidedesign parameters for the inverter causing the inverter to shut down.

29



Incorrect installation.

o String not correctly wired.

o Not plugged into connectors properly.

o Loose connections.

o No voltage on terminals in PV array combiner box.

o Incorrect DC polarity in circuit.

30

Fault indication : The array current is lowerthan would be expected under high conditionsof solar radiation.

Fault/possible cause/solution

Check if the array is shaded or if there is dirt on it.Remove source of shade or clean.

Defects in module, Strings cables caused by storms orlightning etc. ? Visual inspection, Check strings in PVarray combiner box - Voc, Isc, Impp. Take measurementsin conditions of constant sun, not in changeableconditions. Ideally also test with peak watt meter andcompare with measurements made duringcommissioning.

Disconnected terminal? Loose connectors?

31

Cont…



possible cause/solution.

Defective bypass diodes in individual modules-causedby lightning / voltage surge? Short circuited diodesbridging over cell strings and reducing module output.Use process of elimination-first strings, then modules.

Damage to module or cells caused by lightning. Celldamage may not be visible. Take module outputreading. Replace module.

Short circuit in module junction box due to moisture andcompare with data sheet.

32


Stand-alone system

maintence.







The amp-hour capacity.

The number of amp-hours a battery can deliver, is

simply the number of amps of current it can discharge,

multiplied by the number of hours it can deliver that

current.

Theoretically, a 200 amp-hour battery should be able to

deliver either 200 amps for one hour, 50 amps for 4

hours, 4 amps for 50 hours, or one amp for 200 hours.

38

Battery is not charging.

Battery is not charging Measure PV array open circuit voltage and

confirm it is within normal limits. If voltage is low or zero, check the

connections at the PV array itself. Disconnect the PV from the

controller when working on the PV system.

Measure PV voltage and battery voltage at charge controller

terminals if voltage at the terminals is the same the PV array ischarging the battery. If PV voltage is close to open circuit voltage of

the panels and the battery voltage is low, the controller is not

charging the batteries and may be damaged.

39





2

Essential spare parts.

• Solar module.• Solar array cable.

• Junction Boxes.

• Fuses.

• Switches.

• batteries.

• battery charge controls.

42

Instructions

For each installation provide a separate

a)user manual,

b)technician’s manual and

c)installation manual,

in the language most appropriate to the installation site.

The manuals must include the following information:

User manual:

• Daily, weekly and monthly maintenance tasks

• Health and safety guidance.

43



2

Technicians’ manual:

• Periodic preventative maintenance checks.

• Diagnostic and repair procedures.

• Health and safety guidance.

• Itemized list of spare parts including part numbers.

• Resource recovery and recycling procedures.

44

Installation manual

Installation design rationale.

Site-specific drawings (if applicable).

Full installation instructions, including array siting

recommendations.

Wiring diagrams.

Full commissioning instructions.

Health and safety guidance.

45



2

Supervisory Control and Data Acquisition

(SCADA) System:

The SCADA system shall incorporate integrated systemcontrol and data acquisition facilities.

It should be capable of communicating with individualInverters and provide information of the entire Solar PVGrid connected power plant.

The SCADA shall provide information of theinstantaneous output energy and cumulative energy foreach of the Inverters as well as for the entire powerplant, changing of operator modes.

46

Supervisory Control and Data Acquisition(SCADA) System:

The integrated SCADA shall have the feature to be usedboth locally (at two locations) via a local computer andalso remotely via VSAT or the Web using either astandard modem or a GSM / WIFI modem.

47



2


Examples of bad design /

manufacture / workmanship

Examples of failures

scorched points



2


7,5°C

72,2°C

20

40

60

SP01

Contact problems(thermographic pictures of modules)


Thermographic pictures of modules with different failures







2

Examples of Deficiencies

56


57





3


60

Examples of deficiencies in installation

61



3

Examples of deficiencies in installation

62

63



3

Thermal Images

64



3

Cognizance for site selection

66

Training Need in following areas

• PV System Installer certification programme intended to meet industry

requirement through cooperation with leading PV stake holders, NGO’s

and professional associations

• Work shop for system integrators / artisans @ District level

• Fundamentals of Solar Energy

• Familiarization of - PV Module and its characteristic

- B O S compone nts

• Criticality of integration parameters

• Do’s & Do - not’s of system integration

67



THANK YOU.

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PV Installer Program-Participant Guide

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