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1. DESIGN AND INSTALLATION 1

CONTENTS

2. TEST RUNNING 13

3. MAINTENANCE 19

4. MALFUNCTION, POSSIBLE CAUSES AND REMEDIES 20

z-1 Selection of Pump 1

z-2 Installation and precautions 2

q Model BHS submersible deep well pumps 3

w Model BMS submersible volute pumps 4

e Submersible sewage pumps (Automatic type) 5

r Submersible sewage pumps (Manual type) 6

t Submersible pump mounting/demounting device 7

z-3 Electrode and Float Switch 10

z-4 Motor protector 12

z-5 Connection of Submersible Cables 12

x-1 Sequence 13

x-2 Measuring Water Level in Water Tank 14

x-3 Verifying Rotation Direction 14

x-4 Measuring Total Head 15

x-5 Vibration and Noise 15

x-6 Quantity of Water 15

x-7 Motor Protector check 16

x-8 Verifying Motor Insulation and Conductor Resistance 16

x-9 Testing Voltage 18

c-1 Daily Inspection 19

c-2 Periodic Inspection 19

c-3 Cautions during non-operation 19

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z-1 SELECTION OF PUMP (General Information)qChoose a pump appropriate for liquid handled.

11. DESIGN AND INSTALLATION

Liquid andsolid size

Civil engineeringwaste: Max. size5mm.

Solid wastewater:Max. diameter 80%pipe size; Max.length three timespipe size.

Miscellaneouswastewater: Max.diameter 40% pipesize; Max. lengthtwice pipe size.

Wastewaterequivalent to watertreated by a septictank: Max. size 5mm.

Fresh water

Examples offoreignmatter

Dirt and sand, finegravel, pieces ofbroken concrete, etc.(liquid temperaturebelow 32:).

Human excrement,work gloves, rags,sanitary napkin, vinylstring and bags,wood chips, etc.(liquid temperaturebelow 50:).

Fish bones, garbage,egg shells, kitchengrease, cigarettebutts, matchsticks,toothpicks, hair,string, rubber bands,small sticks, bottlecaps, aluminum foil,etc.(liquid temperaturebelow 50:).

Wastewater notcontaining large-sized solids,rainwater, Springwater, water withfloating oil, watertreated by septictanks.(liquid temperaturebelow 50:).

Fine sand of lessthan 50ppm.

Application

Civil engineeringconstruction sites.Building constructionsites, under-passes.Drainage of springwater in basements,tunnels and mines.Stream waterintakes.Flood control.Agricultural irrigation.

Drainage fromsewage holding tankand kitchens (notequipped withstrainers) in buildingsand sewagetreatment plants.Sewage from poultryand hog farmsSewage from foodplants and variousmarkets. Drainage ofwastewater fromincineration plantsand two-levelcrossingunderpasses.

Drainage fromkitchens (equippedwith strainers) inbuildings,department stores,schools, restaurants,hotels, apartmenthouses, hospitals,plants, etc.,miscellaneousdrainage anddrainage fromfacilities.

Drainage from septictanks. Drainage ofspring water andstanding water inplants and buildings.Drainage of springwater and standingwater in subwaysand tunnels.Drainage of springwater and standingwater at constructionsites. Drainage,transit and agitationof wastewater inplants. Drainage andtransit of water infountains, pools andtanks.

For deep wells; liquidtemperature below25:.

For shallow wells;liquid temperaturebelow 40:.

Model Model ES Model DMLDV

Manual type, Model DL,DML

Automatic type, Model DLA

Manual type,Model DS

Automatic type, Model DSA

Pontos 717

Model BHS

Model BMS,BMSP

64

2 1. DESIGN AND INSTALLATION

wBe sure pump capacity is correct.Should too large a pump be selected, the following troubles can occur:1) The pump will be costly to operate.2) Operation will not be economical because the pump is inefficient.3) Excess water will be discharged, resulting in motor over load.4) The pump may take in foreign matter.5) Pump wear will be excessive.Accurately calculated piping loss plus additional 10% total head will assure correct pump operation.

eInstall pump in a location facilitating maintenance.1) When a building is constructed after pump installation, allow sufficient space for removal of pump.2) A manhole should be located above pump.3) Attach a mounting/demounting device to pump. (See Page 7.)

z-2 INSTALLATION AND PRECAUTIONSIt is recommended the following be checked immediately after the pump is received:1) Model, head, capacity, speed, output, voltage, frequency, etc. on the nameplate are as ordered.2) Possible damage incurred during shipment. Possible loose bolts and nuts.3) All accessories are included.Should there be any discrepencies, contact the dealer immediately.

65

31. DESIGN AND INSTALLATION

qModel BHS submersible deep well pumps

PumpThe pump should befully submerged. Atmaximum discharge,the difference betweenthe water level and thepump suction portshould exceed 2m.

Well casing

Power cable bandSecure the submersible power cable to the discharge pipe witha tape or the like at several positions. If not well attached, thecable will wear easily in as much as there is nothing to supportits weight.Each joint of threaded discharge pipe must be firmly fixed andlocked with setscrews.

StrainerThe pump inlet portshould be separatedfrom the well outlet. If thedistance is insufficient,the pump may suck insand, which will hastenwear.

Power cableWhen installing orlifting the pump, do notpull on power cable.Cable must beprotected againstscratches andabrasion.Do not drop end ofcable in the water.

Operatingwater level

Consideration should begiven to the differencebetween natural waterlevel and level atmaximum discharge.Be sure to measure thewater level at maximumdischarge, since it affectsboth water movementand pump function.

Fig. 1-1

Fig. 1-2

66

4 1. DESIGN AND INSTALLATION

wModel BMS submersible volute pumps

Manhole

A manhole or inspection port should be located directly above the pump. When the Model BMS surface plate is used, the installation floor area should be raised slightly to preclude entry of wastewater and dirt to tank.

Cable band

Secure the power cable to the pipe with cable band, tape,or clip.

Eye bolt

When installing or lifting the pump, use this eyebolt.

Pump

The pump should be installed in the center of the tank where there is least turbulence.Maximum submersible depth of the pump should be 10 meters.

Pump stand

Installation of a pump stand prevents entrance of dirt, sand, etc.

Ground terminal

Be sure to ground pump.

Automatic air vent valveWhen the discharge intake stand is provide with a check valve, facilitate exhausting of air by installing an automatic air vent valve between the pump and the check valve, which will simultaneously cause a vacuum break when stopping the pump.Air exhaust is facilitated by installation of automatic air vent valve between pump and check valve. Vacuum break will simultaneously occur when pump is stopped.

Inflow port

Inflow port must be as far from the pump as possible.

Power Cable

When installing or lifting the pump, do not pull on power cable.Do not drop end of cable in the water.Cable must be protected against scratches and abrasion.

Lowest water level at which the pump can be started

The water level should be higher than the discharge flange surface of the pump.

Lowest water level from which the pump

can be operated

The stop water level of the pump should not be lower than this value.See instruction manual.

Fig. 1-3

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51. DESIGN AND INSTALLATION

eSubmersible sewage pumps (automatic type)

Connection

When pump is connected to a drain, a union should be used. Installing the union near manhole will facilitate hoisting and/or inspection.

ManholeA manhole should be located directly above the pump to facilitate inspection.

Suspending ropeor Chain

Use the rope included when installing or hoisting the pump.Secure end of rope near manhole.

Ground terminal

Power connection

Ensure pump is property grounded.

Power Cable

When installing or lifting the pump, do not pull on power cable.Do not drop end of cable in the water.Cable must be protected against scratches and abrasion.

Cable band

Secure the power cable to the pipe using cable band or tape.

Pump

Install the pump away from the inflow port and the wall so that the float switch will not be directly exposed to inlet water. Set the maximum submersible depth in accordance with instruction manual provided with the pump purchased, since it varies according to model. Be sure pump is in upright position, if used when tilted or horizontal, operation may be unstable.

Lowest water level

Set stop water level to position where there will be no air intake.See instruction manual.

Operating water level

See instruction manual.

Single phase

Three-phase

Make all connections secure.

Fig. 1-4

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6 1. DESIGN AND INSTALLATION

rSubmersible sewage pumps (manual type)

Connection

Position the pipe connection as close as possible to the manhole, since it will facilitate lifting the pump.

Manhole

A manhole should be located directly above the pump to facilitate inspection.

Ground terminal

Ensure pump is properly grounded.

Suspension rope

Use the rope included when installing or hoisting the pump.Secure end of rope near manhole.

Power Cable

When installing or lifting the pump, do not pull on power cable.Do not drop end of cable in the water.Cable must be protected against scratches and abrasion.

Pump

Install the pump away from the inflow port. Set the maximum submersible depth of the pump in accordance with instruction manual provided with pump, since it varies according to model.

Stop level

Do not use an electrode to control water level.Set both operating and stop water levels in accordance with the instruction manual provided with pump since they vary according to the size of the pump, and whether or not a mounting/demounting device is used.

Fig. 1-5

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71. DESIGN AND INSTALLATION

tSubmersible pump mounting/demounting device (QDC:Quick Discharge Connector)Maintenance of a submersible pump for sewage and miscelleneous drainage is difficult due to thelocation and the liquid it handles. Use of the following equipment facilitates pump installation, piping,maintenance and inspection. It is recommended these that either equipment be considered whenplanning installation.(1) Installation

1) Mounting/demounting device(a) Installation1. After completing the foundation, install the device and secure with anchor bolts.

At the same time arrange the discharge piping.Improper piping may cause tilt and impair mounting/demounting function.(It will be more convenient if the foundation area of the device is slightly higher than the bottomof the tank.)

2. Insert the guide (steel) pipe into the guide pin of the device and install a support plate forvertical alignment.

3. Insert gasket between pump and flange, and fasten with bolts and washers provided.

Fig. 1-6

Fig. 1-7

Fig. 1-8

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8 1. DESIGN AND INSTALLATION

4. Remove suspension hook from motor, pass itthrough the ring on the end of the chain, and reinstallhook on motor. (Be sure the hook faces flange face.)

5. Hoist the pump with a chain falls or the like and positionabove support plate.

6. Pass the guide pipe through the sliding guide while slowlylowering the pump.

7. Adjust hoisting position so chain can remain vertical and set thepump on the device.

8. Ensure that support chain and cables, do not interfere with other objects. Installation is nowcomplete.

(b) Hoisting the pumpTo raise the pump for inspection, reverse the afore mentioned procedure.

(c) When installing/removing pump1. In event upward or downward along the guide, is due to the presence of foreign matter, wrong

positioning for lifting, etc. do not stress chain.To avoid damage it is recommended the hoisting position be changed.

Fig. 1-9

Fig. 1-10

Fig. 1-11

Fig. 1-12

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91. DESIGN AND INSTALLATION

(d) Precautions for operation1. After installation, start and stop the pump two or three times prior to regular operation to ensure

all is in order.2. When the pump is reset, foreign matter may be attached to the flange face, and prevent proper

seating.To assure proper seating, start the pump while lowering, set the pump on flange and stop thepump.

3. Be sure to observe the lowest water level; should it fall below the minimum, the pump may notbe able to discharge.If this occurs, reset by raising the pump while operating slightly.

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10 1. DESIGN AND INSTALLATION

z-3 ELECTRODE AND FLOAT SWITCHqUsage classified according to liquid handled

Fresh water: ElectrodeSewage: Float switch

An electrode used for sewage may clog with foreign matter and cause malfunction.

wTypes of electrodes and float switches(1) Type MA Electrode (fresh water) - for deep well

(1) Cord:Polyvinyl chloride(P.V.C.)

(2) Material:304 stainless

(3) Stock length:5m per unit

(4) Resistance of substancea) New electrode - 10 MΩ min. between poles by ground

measurementb) Used electrode - 5 kΩ min. between poles by ground

measurement(5) Well water:

Pure water(6) Operational distance:

Hundreds of meters

(2) Type MB Electrode (fresh water) - for reserve and receiving water tanks

(1) Retainer: Bakelite(2) Fixing bag nut: Ten-cornered 20mm 304 stainless(3) Stainless steel bar: 304 stainless, 6Ø lm unit(4) Stainless steel bar: Bag nut for joint 304 stainless(5) Stainless steel bar: Bag nut for joint 304 stainless(6) Attachment: Screw-in(7) Permissible distance:

a 2000m of three-core antennab Buried/piping wiring work: Several hundred meters

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111. DESIGN AND INSTALLATION

(3) Float switch for sewage (Model EF-4)¡Features

1. Easy installation. Simple hanging does the job.2. Powerful buoyant force provides dependable operation.3. Triple switch protection prevents shock hazard.

¡SpecificationsContact: Contact A (Up=ON; Down=OFF)

Operating voltage: AC24V, DC24VNote: For safety, it is recommended voltage should be less than 24V.

Maximum current: AC0.5A, DC0.5AContact capacity: AC12VA, DC12VA

ON-OFF operatingangle: Within 60°

Maximum operatingtemperature: 50:

Pressure resistance: 1kgf/cm2GCable: two core x 0.2mm2 x 6m

Weight: 0.65kgf

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12 1. DESIGN AND INSTALLATION

z-4 MOTOR PROTECTORqMCB (Molded case Circuit Breaker)

The characteristics of MCB rating are accordance with general-purpose motors, this device cannot beused to protect submersible motors. The use of thermal relays to the 3E relays of the motor itself isrecommended.

wThermal relaya. Setting

Use a screwdriver to align the dial with the set pointer.b. Normal condition

Return lever does not project.c. Abnormal condition

Return lever projects.d. Return method

Depress the return lever in the direction of the arrow after having checked for, and repaired, possibledefects.

z-5 CONNECTION OF SUBMERSIBLE CABLESAs a rule, submersible cables should not be connected under water since poor connections will causeunexpected accidents due to submerged cores. If cable length is specified when ordering a pump, themanufacturer will include the connected and extended cable. (Model BHS)Cut the cable proper length for connection to the switch board. If the cable is connected while wound onthe drum, the insulation may break down due to heat.

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132. TEST RUNNING

x-1 SEQUENCE

1 to 3 : Pre-operational inspection4 to 9 : Check during operation

Insulation resistance3

Check the insulation resistance of the motor, including cable, it should be at least 1 MΩ. (See Page 16.)

Automatic Operating water level6

(See Page 3 to 6 and instruction manuals pertaining to various models.)Ensure water level is above that for normal operation, and that air is not drawn into the pump.

Checking the head5

(See Page 15.)

Quantity of water9

(See Page 15.)

Water tank interior1

Check the interior of the water tank to determine if the water level is above that for normal operation. (See Page 3 to 6 and the instruction manuals pertaining to the various models.) Check for possible foreign matter in the pump. (See Page 1.)

Motor protector2

Ascertain setting is proper for motor rating. (See Page 16.)

Checking voltageand current7

(See Page 18.)

Possiblevibration/ noise8

(See Page 15.)

Rotation direction4

(See Page 14.)

Fig. 2-1

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14 2. TEST RUNNING

x-2 MEASURING WATER LEVEL IN WATER TANKqDeep well water-level measurement

Bare the tip of the two-core covered wire and lower into the well; upon contact with water it will becomeconductive. Check for conduction with a multi-meter. Water level is determined by measuring length ofthe wire from the ground to water surface.

wExercize care when measuring water levelWater level should be measured while operating the pump as well as when it is stopped. In particular,water level during operation has a direct influence on pumping action. Be sure to take this measurement.

x-3 VERIFYING ROTATION DIRECTION

qWith pressure gauge1) Open the valve on pump discharge side slightly (one or two full turns) and operate pump.

Pressure gauge reading is denoted as P1.2) Operate pump with motor wiring changed as shown in the following figure (leave the valve open).

Here, pressure gauge reading is denoted as P2.3) Compare P1 with P2.

The reading showing the higher value indicates correct rotation.

wWithout pressure gauge1) Fully open discharge valve, operate pump and check quantity of water.2) Change rotation direction as shown in the above figure, operate pump again and check quantity of

water.3) The largest quantity of water indicates correct rotation.

Connection between Power Source and Motor Cables (three-phase)

Fig. 2-2

Fig. 2-3

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152. TEST RUNNING

x-4 MEASURING TOTAL HEADTotal head of pump in operation is calculated as follows:

Total head=Reading of pressure gauge + HsHs: Vertical distance (m) from gauge to operating water level.

x-5 VIBRATION AND NOISEqNoise during operation

1) Any abnormal noise emanating from the interior of the water tank may be caused by reversed rotation,presence of foreign matter, strainer clogging, etc. Hoist pump and inspect. If noise develops after asubstantial period of use, the cause may be wear.

2) Surface noise may stem from resonance of piping or foundation. Use of flexible joints in piping or theplacing of a rubber mat under manhole will prevent this type of noise.

wNoise when stoppedIn most cases this type of noise is caused by water-hammer. As a countermeasure, it is recommendedthe check valve on the discharge side be replaced with an fast closing check valve.

x-6 QUANTITY OF WATERIt is difficult to measure the quantity of water discharged from the pump at the worksite. It can be estimated,however, on the basis of the measured value of the pump head and the characteristics curve of the pump.

Fig. 2-4

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16 2. TEST RUNNING

x-7 MOTOR PROTECTOR CHECKMake sure the capacity of the motor protector and check it appropriate for the motor used.Be sure the voltage, phase and frequency are correct by checking the name plate. Avoid trial operationusing a temporary power source. Temporary sources often have unstable voltage or lack protection,leading to accidents.

x-8 VERIFYING MOTOR INSULATION AND CONDUCTOR RESISTANCEqTesting insulation resistance

Measuring instrument: Resistance tester (500V cap.)Measured values: As shown in the following figure...Standard judgement.

wCautions(1) To measure motor insulation resistance, disconnect motor lead from the control panel and take

measurement using the end of the power cable.(2) Consideration of measured values.

1) When, despite proper insulation resistance, the motor fails to start, conductor resistance must bemeasured, because either the coil is defective or the power cable is broken.

2) Since insulation resistance value varies, according to conditions, a sudden drop indicates potentialtrouble.It is therefore necessary to implement appropriate countermeasures, such as reducing the loadafter the occurrence of this phenomenon.When using a volute pump, for example, the valve on the discharge side should be slightly closed.

Fig. 2-5

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172. TEST RUNNING

* Example

Pump 1 Pump 2Oct.1 5MΩ 10MΩNov.1 5MΩ 5MΩ

Measurement on Nov. 1 showed the values of both models were 5MΩ.The value of Pump 1 remained unchanged, while that of Pump 2 changed from10MΩ to 5MΩ.This is an indication of trouble and appropriate action should be taken.

eMeasuring conductor resistanceEquipment: Multi-meterMethod: Stop the motor, disconnect motor lead from the control panel, set tester range to Ω, and

measure the resistance between U-V, V-W and W-U using the end of the motor cable. Allvalues should be approximately the same.

¡Since motor coil resistance varies according to output and usually indicates several Ω values, it isdifficult to make precise measurements with a multi-tester. Thus measured values merely determinemotor condition.

* Based on measurements, decisions can be made as follows:

For break of motor coil

When the coil is broken between U and V, resistance between U and Vbecomes twice the value of the other two phases.Example: UV=4Ω

VW=2ΩUW=2Ω

When the two phases of the coil are broken (between U-V and V-W),resistance value between U-V and V-W becomes ∞Ω. Resistancevalue between U-W may have several Ω values.

Fig. 2-6

Fig. 2-7

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18 2. TEST RUNNING

x-9 TESTING VOLTAGEqMeasurement at R.S.T. terminals

This measurement determines if there are abnormalities in the power source of the primary side from thecontrol panel. When measuring R-S, S-T and R-T with a voltage tester, each value should be within±10% of the regulated voltage. However, when the measured voltage is unbalanced (more than 3%),current may become excessive.If voltage decreases during operation, it is probable that the cable is either too small or the power beingreceived is insufficient.Inspection is recommended by a competent electrician.

wVoltage measurement at U.V.W. terminalsWhen there are no voltage abnormalities at R.S.T. terminals, the voltage should be checked at U.V.W.terminals with the control panel activated.Ensure measured voltage is within ±10% of normal voltage and that the balance between each phase isproperly maintained.

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193. MAINTENANCE

c-1 DAILY INSPECTIONCheck for pump head, voltage current, possible vibration and noise. Should abnormalities be detected, itis important corrective action be undertaken promptly in accordance with the procedure described in theinstruction manual.It is recommended that an operation log be kept.

c-2 PERIODIC INSPECTIONqMonthly

Measurement of motor and cable insulation resistance.wAnnual

Oil change.Turbin oil #90 is sealed in the mechanical boxes of Models DS, DN,DL, and DV. If the pump is hoisted to the ground and the oilchanged once a year, the life of the mechanical seal well be greatlyprolonged.(For oil change, follow the instruction manual provided with eachmodel.)

eOverhaulIf the pump is overhauled once every three to five years, it can beused without worry for a long period of time.

c-3 CAUTIONS DURING NON-OPERATIONqNon-operation for prolonged periods while underwater:

Operate the pump once a month to prevent moving parts fromrusting. Take periodical measurements of motor insulationresistance.To resume operation, follow procedure described in Paragraph 3,"Test Running".

wStorage of pump above ground:Clean the pump strainer, and store in a dry place. To resumeoperation, follow procedure described Paragraph 3, "Test Running".Since a submerged type motor is used for Models BHS and BMS, acheck for sufficient water must be made before reinstalling thepump. If insufficient, fresh water should be supplied.To confirm water quantity and supply of fresh water, refer to theinstruction manuals supplied with each model.

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20 4.MALFUNCTION, POSSIBLE CAUSES AND REMEDIES

Magnetic contactor is properly set.

Magnetic contactor not set. Inspection

made by competentelectrician.

Inspection made by competent electrician.

Pump fails to start.

Ensure motor protector in control panel is operating. (See Page 12.)

Protector is not operating. Protector operating.

Manually operate pump. Restore protector to original position and re-start. (See Page 12.)

Pump fails to start.

Pump start. Protector operates the moment switched on.

Occasionaloperate.

Activated several seconds after switched on.

Malfunction in automatic control equipment, liquid surface relay, float switch, pressure switch, etc.

Remove motor cable from power board and measure voltage at power board terminals, U, V, and W. (See Page 18.)

Check current.

Normal.

Normal.

Abnormal.

Abnormal.

Abnormal. Normal.

Normal. Abnormal. Abnormal.Normal.

Check for proper setting of magnetic contactor.

Inspection made bycompetent electrician.

Measure insulation resistance and conductor resistance at motor cable terminals. (See Page 16.)

Abnormal componentspertaining to or power source.

Ensure proper set value of protector and determine whether value agrees with motor rating.(See Page 12.)

Measure voltage at motor cable terminals, U, V, and W, of control panel. (See Page 18.)

Check terminals, R,S,and T, for voltage.(See Page 18.)

Set value agrees with motor rating.

Set value does not agree with motor rating.

Defective motoror cable.

Pump ormotor is mechanicallylocked.

Defective protective device.

Faulty setting.Reset.

Cable trouble between controlpanel and motor or motor protectoris operating.

Malfunctioninsidecontrol panel.

Power sourcetrouble.

Lift pump replacecable or motor.

Lift pump and overhaul it.

Replaceprotector.

Lift pump and overhaul.

Inspection madeby competent electrician.

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214.MALFUNCTION, POSSIBLE CAUSES AND REMEDIES

Cloggingof pump and strainer.

Pump fails to function despite motor operation.

Check rotation direction.(See Page 14.)

Proper rotation.Reverse rotation.

Check water tank for waterlevel. (See Page 15.) Change to proper rotation.

Interchange two wires of the three-phase motor and reconnect.(See Page 14.)

Below minimum water level required by pump.

Above minimum water level required by pump.

Air suction.

Measure shut-offpressure of pump.

Raise water level in tank.

Normal. Low.

Open discharge valve slowly.

Wear of pump interior.Enlargement of inside clearance.

Leak in the pipe between pump discharge port and gauge.

Almost the same as shut-offpressure.

Sudden decrease in pressure.

Equipmenthead is too high.

Clogging of discharge pipe on outlet side of pressure gauge.

Air accumulation in pump.

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22 4.MALFUNCTION, POSSIBLE CAUSES AND REMEDIES

Clogging of thepumping pipe.(between the gauge and pump.)

Insufficient water and pressure.

Check rotation direction.(See Page 14.)

Proper rotation. Reverse rotation.

Check shut-off pressure with discharge valve fully closed.

Interchange two wires of the three-phase motor and reconnect. (See Page 14.)

Shut-off pressure is normal. Insufficient shut-off pressure.

Open discharge valve fully. Air accumulation in pump. Wear of pump interior.

Compare working gauge reading with the rated value.

Operating head is greater than that specified.

Operating head lower than that specified.

Clogging of discharge pipe.

Equipment head too high.

Clogging of pump and strainer.

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234.MALFUNCTION, POSSIBLE CAUSES AND REMEDIES

Specific gravity of pumped water too great.Sand mixed with water.

Excessive current.

Check rotation direction.(See Page 14.)

Proper rotation. Reverse rotation.

Measure current with discharge valve fully closed.

Interchange two wires of three-phase motor and reconnect.

(See Page 14.)

Normal. Abnormal.

Excessive water.

Adjust discharge valve opening so that currentagrees with rated value.

Refer to"Pump fails to start."

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24 4.MALFUNCTION, POSSIBLE CAUSES AND REMEDIES

Resonance in pipeline or foundation.

Vibration and/or noise.

Check rotation direction.(See Page 14.)

Proper rotation. Reverse rotation.

Check areas generating vibration and/or noise.

Interchange two wires of the three-phase motor and reconnect. (See Page 14.)

Pump and related parts. Room interior, foundation, and pipeline.

Clogged strainer.

Clogged pump.

Wear of pump interior.

Water-hammer.

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