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Choosing your traction battery and charger
Traction batteries - general
Choosing your battery
Life factors
Chargers – general
Charging process - general
Oxyhydrogen gas – oxygen and hydrogen
Topping up
Water quality
Maintenance
Notes
1
Index ................................................................................................................ 1 Choosing your traction battery and charger ............................................... 2 Traction batteries - general .......................................................................... 3 Construction...................................................................................................... 3.1 Battery size ...................................................................................................... 3.1 A little battery chemistry .................................................................................. 3.2 Pause charging................................................................................................. 3.3 Self-discharge................................................................................................... 3.4 Cold stores ....................................................................................................... 3.4 Choosing your battery .................................................................................. 4 Standard battery ............................................................................................... 4.1 Acid circulation battery .................................................................................... 4.1 CSM (Copper Stretch Metal) battery ................................................................ 4.1 Construction of a CSM battery ......................................................................... 4.2 Dryfit battery, VRLA maintenance-free ........................................................... 4.3 Life factors ..................................................................................................... 5 How long does a battery last? .......................................................................... 5.1 Definition of a cycle ......................................................................................... 5.1 What affects the life of a battery?..................................................................... 5.2 Why is too much current used?........................................................................ 5.2 When does a battery sulphate?........................................................................ 5.2 Chargers - general ......................................................................................... 6 W charge characteristic .................................................................................... 6.1 I charge characteristic ...................................................................................... 6.1 Examples of constant current charging profiles ............................................. 6.2 Charging process - general .......................................................................... 7 Oxyhydrogen gas – oxygen and hydrogen.................................................. 8 Topping up ...................................................................................................... 9 Manually ........................................................................................................... 9.1 Automatically ................................................................................................... 9.2 Water quality .................................................................................................. 10 Maintenance .................................................................................................... 11 Daily ................................................................................................................. 11.1 Weekly ............................................................................................................. 11.2 Monthly ............................................................................................................. 11.2
2
Choosing your traction battery and charger The battery is the heart of your truck
A healthy heart means good quality of life. An unhealthy heart means poor quality of life.
Your doctor gives good advice when he says, “You should use your heart, but not abuse it.
You should load your heart, but not overload it.” Replace the word "heart" with the word
"battery" and you have some good advice from your battery supplier.
Without food and drink, even a genius can’t think
Good, sensible dietary habits prolong your life and allow you to be more active. The right
current in the right quantities prolongs the life of your battery and allows it to achieve optimal
performance throughout its life.
Therefore, you should always choose a battery that is big enough for the type of truck and
the work for which it is intended. Always use a charger that is correctly dimensioned and
gives the battery precisely the right, optimal charge.
Brains and brawn
– the right combination of charger and battery makes your life easier Size (capacity) should not be the only factor that influences your choice of a new battery. The type also plays a very important part in efficient operation and long life.
3. 1
Traction batteries - general Construction
A traction battery consists of a number of individual cells, each of 2 volts. For example, a 48-
volt battery consists of 24 cells connected in series, each with the same capacity (Ah). The
cells consist of brown positive filled tubes and grey negative lubricated plates that contain
various lead alloys (tubular plate batteries). Unlike starter batteries, which contain positive
plates, a truck battery consists of positive tubes. This is because a starter battery has to be
able to supply all its current for a short period of time to start a vehicle, while a traction
battery has to be able to supply its current over a longer period of time in order to be able to
last a full working day.
The electrolyte, which causes the electrical tension between the positive and the negative
terminals, consists of diluted sulphuric acid.
Example
A 48-volt/500-Ah battery consists of 24 cells connected
in series and enclosed in a painted or Levasint-coated
battery case, normally made of iron. Each cell is a 2-volt
cell and has a capacity of 500 Ah, which means that,
roughly speaking, the battery can supply 100 A non-
stop for 5 hours, equivalent to the nominal 5-hour
capacity. If, for example, 200 A is consumed per hour,
the battery can only operate for around 2 hours and not
2.5 hours, as you might think.
The faster a truck battery’s current is consumed, the lower its useful capacity.
Battery size
When a truck works, it consumes current from the
battery. The battery is emptied and must then be
recharged. We call this discharge and charge process
a battery cycle. The more current a piece of work
requires, the higher the battery capacity must be
unless its lifecycle (life) is reduced.
The truck’s battery compartment determines the
physical size of the battery. The larger the battery
compartment, the more capacity the truck battery can
have. The individual cells which make up the battery
are therefore produced in many different heights and widths. A large cell volume, which
means a lot of active material, produces a high battery capacity. GNB Industrial Power, for
example, has more than 150 different cell types in its standard range.
Above you can see a small selection of different traction cells that can be combined in the
thousands of different battery cases designed for all truck types produced worldwide.
3. 2
A little battery chemistry
In a new, charged lead/acid tubular plate battery, the plates are "clean", which means that
they have been cleaned of acid residue (sulphates), and the acid density is correct, normally
1.29 g/cm3, also expressed as 1290 g/l.
When the battery is being discharged, the lead plates use the free surrounding sulphuric
acid to send current out into the system. At the same time, some acid residue remains, the
so-called sulphates. The sulphates are deposited on the plates and reduce the area
available for the production of current, which finally stops altogether, and the battery is fully
discharged and sulphated.
Sulphates are
dissolved Density
increases
Sulphates are
dissolved
Plates
sulphateDensity
decreases
Plates
sulphate
Voltage increases Voltage decreases
ChargeDischarge
The plates in a discharged battery are therefore full of acid residue, and the acid density (g/l)
has decreased greatly on account of current production. When the battery is then charged,
the sulphates are broken down and the acid residue should combine with the very weak acid
in the battery.
However, the acid residue, which is much heavier than the surrounding liquid, falls to the
bottom and is therefore of no benefit to the cleaned plates. So the charger continues with a
gassing charge, whereby the current charged is mainly used only to agitate the acid in order
to move the heavy acid residue up in the cells and into contact with the somewhat more
dilute acid at the top of the battery. When the charger shows that it has finished, the plates
are clean and the acid is evenly distributed throughout the battery.
When a truck battery is in use, current production takes place where there is least resistance
and the distance to the surrounding acid is shortest, i.e. the distance from the surface of the
plates. As the surfaces sulphate, current production moves further and further into the plates
and finally it stops altogether. The battery is charged in the opposite order.
3. 3
Pause charging
If a partially discharged standard battery is pause charged, parts of the plates are cleaned
and are ready for use. But the clean plates do not have a very strong acid to work with as
the heavy acid residue has fallen to the bottom of the cells. This acid residue is not mixed
with the dilute acid until the gas point is reached and the gassing charge starts. Pause
charging is fine if the gas point is not
reached but the cleaned plates do not
work optimally until the acid has
reached its correct density again.
Therefore, if pause charging is
necessary, choose an acid circulation
battery, a CSM (Copper Stretch Metal)
battery or a charger with chemical acid
agitation.
When can you use pause charging?
Situations arise in which a battery does not have enough capacity for a full day's work. In
order to avoid discharging it more than 80%, it is necessary to use pause charging. The
discharge curves of three batteries are shown below. They can all meet the capacity
requirements for the day, but only one of them is handled correctly from the point of view of
the battery.
Fully
charged Gassing
Char-ging
80% 80% is the
correct depth of discharge
Deep
discharged
PausePause
All three batteries are fully charged at the start of the day and all three have two breaks
during the day. One of them is deep-discharged at the end of the day. This is the green one,
which was not pause charged. The red battery is pause charged during the first break of the
day, with the result that it gasses before it is disconnected from the charger, because more
is charged than is taken out.
The blue battery is only pause charged during the second break of the day, when the truck
driver is certain that the gas limit cannot be reached. Therefore, with a little care and the
correct charger, it can sometimes be useful to use pause charging.
3. 4
Self-discharge
In addition to its normal discharge, a traction battery also has a so-called self-discharge.
There is consumption in both the positive tubes and the negative plates, which just sulphate
on their own. On a daily basis, this is of no significance as the regular charges compensate
for this discharge. However, if the battery is stored for a period of time, it is clear that the
density will decrease. The self-discharge per month is approximately 5-7% of the battery’s
capacity but it depends greatly on the battery's age and the ambient temperature.
Consequently, it is recommended that a battery be stored in a cold, dry and frost-free room
- always fully charged.
Cold stores
When a truck battery is used in a cold environment, its capacity decreases, while the voltage
and the density increase.
This means that cold store batteries must be slightly bigger than normal and the charger and
battery indicator must be adjusted according to the actual average temperature. A normally
adjusted charger will not be able to charge a cold battery fully, which causes the battery to
be sulphated, meaning the capacity decreases further. A CSM battery with an intelligent
charger that can compensate for the temperature is best suited for cold operation.
The effect of the temperature on capacity
Acid temperature Battery capacity
+30°C 100%
+20°C 95%
+10°C 90%
0°C 80%
-10°C 70%
-20°C 50%
-30°C 35%
4. 1
Choosing your battery Standard battery
The standard lead/acid battery has not changed much since it first came into existence more
than 100 years ago. It is the type of battery used most throughout the world and it fully
meets the requirements made of a battery designed for normal operating conditions. If, in
compliance with the warranty, you use 80% of a battery’s capacity of around 5 operating
hours, the equivalent of a normal working day, a standard battery is the correct one to
choose. There is no reason to pay for a better or stronger battery if you do not need it.
Acid circulation battery
If there is not enough room in the truck for a battery that is big
enough for a full day’s work, or if you have less then around 8
hours available for charging, it is often a good idea to choose
an acid circulation battery. This is well suited for pause
charging and charging in as little as 6 hours. You just have to
be aware that, as the battery is too small for the job, it will be
exhausted before time. So its life will be somewhat shorter
than usual, depending on the level of over-consumption.
The advantage of a circulation battery’s “spot charges” is that
the heavy acid that normally falls to the bottom is agitated and
is immediately sent to the top as a result of the air supply
connected to the battery. This type of battery is more
expensive than a standard battery and it needs a special
charger with an air pump that must be purchased with the
battery in most cases. But the alternative would be to buy a
replacement battery.
CSM (Copper Stretch Metal) battery
Less internal resistance and high, stiff voltage make the CSM battery ideal for hard
operation and heavy lifting when you are really in a hurry. The faster current needs to be
consumed, the more suitable a CSM battery is. The resistance in a CSM battery’s negative
copper grids is 13 times lower than in traditional lead grids, which produces an energy gain
of up to 25%. So you get much more energy with the same capacity.
The idea behind the CSM battery
The idea behind the CSM battery is based on Ohm’s Law, which basically says that a
battery’s voltage loss is equal to current multiplied by internal resistance. The lower the
internal resistance, the lower the battery’s voltage loss (heat loss), which now becomes
useful energy instead, meaning a longer operating time.
4. 2
CSM batteries and pause charging
Due to the low internal resistance of a CSM battery, it supplies and collects current faster,
evenly distributed throughout the height and width of the cell. This means that the cell
voltage increases faster, with the result that the energy collected during pause charging is
higher than for a standard battery.
CSM technology was originally developed as a necessity for submarine batteries. Today it
has been patented by Exide Technologies.
The advantages of CSM batteries are obvious
Up to 25% more energy and thus a longer operating time than
standard batteries.
High constant voltage under hard operation compared with a
standard battery, which has a steadily decreasing voltage
throughout the course of operation. This decreasing voltage is
problematic for the truck’s electronics, which will react by
demanding more and more current.
Lower heat generation and thus less damage to the battery
throughout its life.
Construction of a CSM battery
1. Copper Stretch Metal grid 10. Patented terminal
2. Negative leaded CSM grid 11. Cell cover
3. Perforated protective casing 12. Flexible screw connection
4. Separator 13. BFS float
5. Negative lubricated grid plate 14. BFS plug
6. Positive lead grid 15. Seal cover
7. Positive tubular plate 16. Terminal screw
8. Negative plate assembly, Terminal 17. Gasket
9. Positive plate assembly, Terminal
4. 3
Dryfit battery – maintenance-free
Dryfit batteries are closed, valve-regulated (VRLA), maintenance-free traction batteries with
the same dimensions as standard batteries, but the difference is that they have slightly less
capacity per volume unit.
Moreover, these batteries can only be discharged to around 70%, whereas standard
batteries tolerate 80%. This means that the useful capacity of a given truck is much lower
than its nominal capacity. So before you choose a Dryfit battery, you must be completely
clear about the type of operation for which it will be used and you must know the daily
capacity consumption.
The advantages of dryfit
No topping up with water
Saves time and possibly money, as a lack of water shortens a battery’s life.
Lower energy consumption
More economical. Less current used for charging as the battery does not require an
agitation period.
No acid overflow
More economical. No acid in the battery case and on the floor and less cleaning of the
battery.
Virtually no gassing
Environmentally-friendly. Saves money. Smaller charging room and air extraction.
The disadvantages of dryfit
Lower discharge depth
Less economical as a larger battery is required than for open batteries.
Higher price
Less economical as dryfit batteries are generally around 50% more expensive than
standard batteries.
5. 1
Life factors How long does a battery last?
A battery's life depends entirely on how much it is used every day for however many days it
is used. So a battery's life varies from user to user.
A battery’s life in accordance
with the IEC 254-1 standard
5-6 years or 1500 cycles in normal
operation with one outlet and a
discharge depth of max. 80% per day.
The life of a dryfit battery is around 1200
cycles, but it may only be discharged to
0-75%.
finition of a cycle
7
De
a
,
d when
e next day's work begins.
discharge depth constitutes a deep discharge and invalidates the
attery warranty.
t for a full day’s work and you are certain that you will
ot reach the battery's gas limit.
A cycle is a discharge followed by
charge. The more cycles a battery
undergoes in a 24-hour period, the
shorter its life in terms of time. The best rhythm for a battery is one cycle every 24 hours
which means that the battery must be charged when the day’s work is done and when it has
been discharged to max. 80% (dryfit: 70-75%) of its capacity, so that it is fully charge
th
Over 80% (70-75%)
b
In principle, pause charging, i.e. an incomplete charge of a partially discharged battery, is a
permissible option but it also risks the temperature becoming too high or the gas limit being
reached (this counts as 1 cycle). For this reason, pause charging should only be considered
if the battery capacity is not sufficien
n
5. 2
The chart shows the number of cycles aNumber of
cycles battery contains throughout its life atvarious discharge depths.
Discharge depth and life:
80% discharge produces 100% life.
90% discharge produces roughly 75% life.
1500
hat affects the life of a batter
Discharge depth in% 60% 70% 80% 90%
W y?
eep discharges:
t, faults, etc.
hy is too much current used?
D Max. 80% depth
Over-consumption: Max. 80% of capa city
High temperatures: Max. 50°C in the acid
Overcharging: Burns the battery out
Undercharging: Sulphates the battery
Maintenance: Incorrect acid level, dir
W
attery too small
at the same time
els)
driving surface
hen does a battery sulphate?
B
Driving and lifting
The truck driver thinks he’s a “racing driver”
Truck fault (wear, brakes sticking, dirt in whe
Too much additional equipment
Incorrect tyre type, ramp driving,
W
it is left uncharged
to 80% every now and again, it gets “sluggish”
erature
he above points are the main reasons why a battery does not last as long as expected.
a
your battery’s life.
If
If it is not discharged
If it is not fully charged
If it works at a high temp
If it is topped up with acid
T
Some of the factors destroy the battery very quickly. Others take slightly longer. However,
common feature of them all is that they can be avoided if you are interested in prolonging
6. 1
As it is the battery that keeps the truck going, users often only focus on the battery, ignoring
the charger, which is usually regarded as just an expensive but necessary evil.
The charger supplies the battery with “fuel”, which, in turn, supplies the truck with energy,
just like petrol in a car engine, and who would put 92 Octane fuel in a 98 Octane engine?
Incorrectly charging a battery will simply destroy the battery bit by bit, or possibly even very
quickly.
So it is very important to be quite clear what performance you require of your battery pack
now and in the future. Hard operation or normal operation? How much time do you have
available for charging? Do you work for a few hours a day or around the clock? These
questions should be answered before you buy a charger.
Chargers - general
6. 2
Two types of charger are available today, “W”
constant-effect-chargers and “I” constant-Charging process
current- chargers.
W charge characteristic
A constant-effect-charger generally produces
the same effect (W) throughout the charging
process, which produces a decreasing current
characteristic. This means that, as the battery
voltage increases, the current decreases until
the voltage reaches the gas limit of roughly 2.4
volts per cell (V/c), at which point water begins
to divide into oxygen and hydrogen.
The current then decreases to roughly 25% of the charger’s rated current value, after which
it stabilises until the charging has been completed. This phase is called the gas phase.
When the battery is fully charged, the charger stops. Most chargers will then start a
maintenance charge which may be either constant current or current pulses that maintain
the battery’s voltage level.
I charge characteristic
A constant-current-charger produces the
charger’s rated current throughout the bulk
charging process until the gas limit of roughly
2.4 V/c has been reached. The charge
with constant voltage of 2.4 V/c until the
current is so low that the actual gas phase
ne of the many advantages of constant-current-chargers is that the battery is generally
fully charged when the gas point is reached. This means that the charging time is greatly
reduced. These chargers are also based on the microprocessor principle, which means that
the charging process is read off continuously and the charging is adjusted in line with the
readings. The latest of these chargers are high-frequency (HF) chargers, which cause the
battery the least damage.
Charging process
W-characteristic
IUI-characteristic
characteristic varies somewhat after this,
depending on battery type.
In the graph to the left, the charger continues
can start.
O
6. 3
Examples of constant-current-charge curves
2100 HFP hig n tubula te batteries
- IWa charging profile
Constant current until the battery is almost ch rrent until the
voltage has become constant for a given peri d of time. 10 min. maintenance charging every
6 hours.
2100 HFP high dryfit tubular plate batteries
- IUIU charging profile
Constant current until the voltage reaches 2.3
has decreased to 10% of the nominal value. T fully
charged. Constant maintenance charging so V/c.
he above are just two examples of charging profiles for an open battery and a closed
battery. However, the battery suppliers’ prescribed curves may be different so it is a good
idea to check the profile for any existing charger if it is subsequently connected to a new
battery.
h-frequency for ope r pla
arged. Then decreasing cu
o
-frequency for closed
5 V/c. Then constant voltage until the current
hen constant current until the battery is
that the cell voltage does not fall below 2.3
T
7
neral Charging process - ge Bulk charge
ly
ffect-charger during this phase.
Gassing charge
The charging time is from when the charger is started until the gas point at approximate
2.4 Volts per cell is reached. A constant-current-charger charges up to 20% more than a
standard e
The charging time from when the gas point is reached until the charge is finished varies from
charger to charger. Some gas phase times are a percentage of the main charge time and
others are controlled by the microprocessor's program.
Maintenance charge
When the battery has been fully charged, most chargers continue with some form of
maintenance charging to counteract the battery's self-discharge.
qualising charge
E
ammed to continue charging with a weak current for a number of
ours in order to adjust any cells that have too low voltage.
Always remember to switch the charger off or press the pause button each time the battery is disconnected from or connected to the charger
If the charging connectors are disconnected live, sparking may occur.
Some chargers are progr
h
8
Oxyhydrogen gas – oxygen and hydrogen
s disconnected from the charger before the charging process is finished will
sually emit gas. A battery that is fully charged with the cover closed will take a long time to
battery that explodes will most probably burst the cell covers and expel acid out into the
urrounding area. If there is anyone nearby, they will be hit by the acid.
the event of an accident, the acid can be adequately neutralised with plenty of running
Avoid cigarettes, sparks and open flames near the
Your eyes are most at risk, so you should always use protective goggles. There
A battery that i
u
emit its gases. This means that the air around the battery is full of hydrogen gases that
explode on contact with the slightest spark.
A
s
In
water, followed by an immediate visit to a hospital accident and emergency department.
NB!
battery
must be an eyewash bottle near the charger.
9. 1
“die” very quickly. To avoid this, it is necessary
top up with water occasionally, but only with demineralised water.
Topping up When a battery gases, water disappears and not acid.
This means that the acid concentration increases in the remaining liquid and the plates are
no longer covered. This causes the battery to
to
Water can be added in many different ways, for example:
Manually
A simple water bag with a hose and a
gate valve.
A watering can with a standard spout.
A watering can with a self-stopping
il” with a filling
ut never use equipment in which the
ater can come into contact with metal
s otherwise it will immediately
nised.
AccuPub with LED filling gun
spout.
An inflatable “HandyF
tube and manual water cock.
B
w
a be
io
Still manual, but the easiest method on the
ts of a filling
r out through an
ch cell reaches the
gun
ater supply.
pacers, the AccuPub can be
used for all cell types.
No overflow of water or destructive acid.
Always uniform, equal acid level in all cells
after each top-up.
Stops topping up itself when the cell is full.
No extra accessories or equipment on the
batteries.
Can be used for all makes of battery by
just replacing the spacer.
market. The AccuPub consis
trolley that pumps the wate
optical filling gun. When ea
correct liquid level, the filling
automatically shuts off the w
Using various s
9. 2
Automatically
anual topping up is time-consuming. Therefore, several different automatic systems are
vailable today that can make life easier for the people who look after batteries on a daily
hoses that are connected to a
entral, mobile or permanently installed water supply. Automatic topping-up plugs shut off
ating plugs that are connected to each other via plastic
entire system ends in a quick-acting coupling that must be connected to a
uitable water supply. The three known systems available on the market today work in
different ways. However, the principle of the p gs and the hose connection is a common
feature.
The BFS system
M
a
basis. Automatic topping up takes place via cell plugs on
c
the water when the cells are full.
All cells in the battery have level-regul
hoses. The
s
lu
The BFS system is the most widely used syst
a high place which can provide a pressure of
pply
on is a standard 25-
of
u are advised to
use a mobile water trolley.
Th 4 cells with the BFS- system mounted
Indicator cylinder
Valve cylinder
Water cylinder
Gassing cylinder
T cylinder for water connection
e picture shows
The picture shows the structure of a BFS plug
em. A BFS water trolley or a water container in
between 0.3 and 2 bar (min. 3 m height) is
required as the water su
source.
If you only have a few
batteries, the simplest
soluti
litre water container with a
hose and a quick-acting
coupling.
If you need to top up a lot
batteries, yo
9. 3
ystem The Aqua Jet s
tank are also
quired.
When the topping-up tank is full and pressurised,
the hose system is connected to it and the battery
is ready for use in less than 30 seconds.
The Aqua-Jet system is the fastest topping-up
system on the market and works at high pressure.
The battery cells are connected by hoses in this
system. An external water supply and a pump that
can create the right pressure in the
re
The Autofil system
he Autofil system also has the battery cells
onnected by hoses, and has an external topping-
p trolley or a wall-mounted box that to
attery using negative pressure, unlike the other
The following applies to all systems:
Only top up with demineralised water.
T
c
u ps up the
b
systems.
The Autofil system, which used to be very popular,
is in the process of disappearing from the market.
10
ity Water qual mS - microSiemens
d water is at 0-5 mS. However, if it is placed in clear containers, its mS value
ill gradually increase so much that it cannot be used for batteries. This is because of the
sable to use coloured containers or dark
eriod of time.
the water comes into contact with metal, for example taps, pipes or topping-up heads, the
ater’s value increases to 50-60 mS, which is unacceptable. The water should preferably
ot exceed 10 mS and must never exceed 20 mS.
you have a lot of batteries and use a lot of water, it may be worth buying your own
emineralisation system.
Normal tap water is usually around 250 microSiemens.
Demineralise
w
liberation of salts by bacteria. As a result, it is advi
rooms if the water is to be stored for an extended p
If
w
n
If
d
11. 1
Maintenance Prevention is better than cure
Make sure at all times that your battery is "in good health". Visible defects and deficiencies
ust be remedied immediately to avoid subsequent high repair costs which could easily
ded by spending a few
inutes a day on the battery.
addition to the battery care mentioned above, there are a few things that must be done
charger arging
t must
er or e button.
y and close the
ttery connector
m
have been avoided. A defective cable will result in unnecessarily high current. Dirty, damp
cell covers will result in leak current and drain current from the battery. Acid overflow will
reduce the battery's capacity and break down the battery case. Too little liquid in the cells
will sulphate and damage the battery. All of the above can be avoi
m
If you check your battery and remedy any faults in time, you will prolong its life.
In
every day, every week and every month.
M
Check that the has finished chthe battery.
The green lighbe on.
Switch off the chargpress the paus
Wipe the batterbattery cover.
Connect the bato the truck and drive off.
orning
When you start work –
Daily Evening
– When you stop work
Drive the truck close enough to the charger that the battery connector and the charger connector can easily reach each other.
Turn the ignition key and switch off the current.
Open the battery cover so that the gases can escape during charging.
Connect the charger connector to the battery connector.
Switch on the charger if it has a switch.
Check that the charger starts before leaving it. The red light must be on. Some chargers have a yellow light.
d the charger
cables.
Disconnect the batteryconnector anconnector.
Do not pull the
11. 2
Maintenance
Check (every Friday, for instance) that the acid level is above the fore charging the battery. If the acid th demineralised water so that the
is too low, top it up with etres
the cells, time the battery is charged.
s, cable terminals and connectors. d immediately. Ensure that the cell he battery wit nd hot
rrect level after charging has
perature in the centre cell e battery is fully charged and idle. The temperature must not
ly be around 30°C. Then measure lls and note the maximum and
ween tdergo an equalisin
g on the age of the battery. The tionship between density and se as the temperature decreases.
Weekly
Monthly
lead plates and separators belevel is too low, top it up wi
ttery is idle. If the acid level
they will “boil over” the next
Check the cell connectionAny defects must be remedieplugs are closed. Then wash twater and wipe it dry. Use protective goggles.
Top up with water to the cofinished.
acid just covers the plates but is no higher. If you charge a battery with an acid level that is too high, the acid will overflow down into the battery case. If this happens too frequently, the battery will require acid adjustment. If you charge a battery with exposed plates, the battery will gradually be ruined. Then check the acid level mid-week after charging when the bademineralised battery water until the acid is 1-2 centimabove the plates. If you pour too much water into
Always use approved demineralised battery water.
h a brush a
NB!
Measure the temth
of the battery when
exceed 50°C but will normalthe density or voltage in the ceminimum values. If the difference betgreat, the battery must un
pendin below shows the rela
ncreainal value.
hese values is too g charge to
equalise the cells, detablevoltage. The values i30°C is the nom
Temp. Density Volt
0°C 1.31 2.15
15°C 1.30 2.14
30°C 1.29 2.13
45°C 1.28 2.12