6.1. Periodic maintenance
Under normal operating
conditions, when charging
recommendations are respected,
and correcting factors are
applied, low maintenance STM
batteries require no regular
maintenance apart from topping-
up (see chapter 6.2.).
A brief overall inspection of the
battery system during a general
revision of the vehicle should be
carried out. The following points
are to be verified:
• the state of the fans, if present,
• the tightness of the connections,
• the seal of the hydraulic circuit
(filling, cooling),
• cleaning the batteries with
soapy water (detergents must
be avoided).
The verification of the electrolyte
density is both unnecessary and
impossible.
6.2. Topping-up operation
!
Measuring the electrolyte level
Topping-up with distilled or
demineralized water (for water
quality refer to chapter 2.2.)
is necessary, because Ni-Cd
batteries consume water through
electrolysis during overcharge.
The electrolyte level is visible
through the plastic container of
the STM 5-100 MR monoblocks
during charge. The electrolyte
level is not visible in the
STM 5-100 MRE monoblocks due
to the double walls of the fluid
chambers, and barely visible in
the STM 5-140 MR monoblocks.
The only reliable time to measure
the electrolyte level is at the end
of charge or a few minutes after
the end of charge (when the
electrolyte is at its highest level).
In practice, topping-up is done
according to overcharged
amperehours.
!
Frequency of topping-up
After a number of cumulated
overcharged amperehours
according to model:
• STM 5-100 MR et MRE:
1 000 Ah overcharged
• STM 5-140 MR:
800 Ah overcharged
!
Topping-up operation
&
Topping-up must not be carried
out during the first 30 minutes
after the end of an overcharge
(1), but it can be carried out
during a peak charge period
and after its controlled term (2).
Water is filled into the hydraulic
system from a reservoir by gravity
or by vacuum, according to
the principles described in
chapter 1.4.
When topping-up is effected using
gravity, the flow rate at the inlet
must be between 0.7 and
1 liter/minute and the relative
pressure at the inlet of the first
cell of the first monoblock must
be less than 0.15 bar relative.
Stop filling a few seconds after
water spills over at the vent
pipe(s). The inlet pipe will close
and the flow of water will stop
automatically when the inlet
connector(s) are being removed.
When topping-up is effected using
gravity, the flow rate at the inlet
must be between 0.7 and
1 liter/minute and the relative
depression in the monoblock must
be less than or equal to 0.3 bar.
6. Maintenance
18
(1) During the first 30 minutes following
the end of the overcharge, the residual
gases from the overcharge process can
disturb the filling operation and, most
importantly, decrease the water quantity
filled into the cells.
(2) After the 30 minutes period following
a controlled term of the peak charge, the
electrolyte level is too low, such that the
monoblocks will be overfilled, thus
seriously risking an overspill of electrolyte
during the following charge and
consequently a dilution of the electrolyte
during the next topping-up.
Summary of Contents for STM 5-100
Page 1: ...Technical manual installation operation and maintenance for Ni Cd STM MR MRE monoblocks type ...
Page 23: ...Appendix 1 20 Monoblock STM 5 100 MR G RD equipped Positive left Filling right ...
Page 24: ...21 Appendix 2 Monoblock STM 5 100 MRE G RD equipped Positive left Filling right ...
Page 25: ...Appendix 3 22 Monoblock STM 5 140 MR G RD equipped Positive left Filling right ...
Page 26: ...Appendix 4 23 Monoblock STM 5 140 MR D RG equipped Positive right Filling left ...