Manual
Operation Manual for
ZeMa Single Cells
Prepared on: 23-11-2022
Prepared by: GBA
Released on: 04.01.2023
Released by: -
Revised on: -
Index: _-
Distributed to: customer (public)
Pages: 30/35
This document is uncontrolled when printed. For the most current and official copy, check the server.
Rail Engineering
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Fax +49 (0) 2331/372 804
DE-58089 Hagen
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12. Troubleshooting
Rolling stock batteries with 2V ZeMaRail single cells will operate very reliably if the
charging conditions are correct and correctly adjusted to the operating conditions in the
train.
12.1.1 A failure of an individual cell or the battery usually leads to a reduced capacity of total
battery and appears to the operator in a reduced backup time in battery mode (“Battery
Load groups will switch off faster because the battery discharge voltage U
final
is
reached earlier or
Too little capacity for lifting the pantograph or starting up of the train. (The battery
would respond to the higher power consumption with a voltage dip).
A BMS (Battery monitoring system) could detect an unbalanced behaviour between
individual battery parts if the discharge voltage of a single cell drops down too early.
12.1.2 To allow later analysis, we recommend in case of a failure to measure and record the
individual cell voltages. We also recommend recording the conditions under which you
made these measurements:
Was the battery charging or discharge current or is the battery disconnected from the
vehicle (if so what was the duration?)
Estimated state of charge of the battery
Temperature of the battery. Pay attention to deviations of individual cells.
Low voltages of individual cells during discharge can indicate an internal cell short-
circuit or over-discharging.
12.1.3 Following such a failure, it is recommended to charge the batteries as soon as possible.
According your operating conditions decide whether this charge should be made in the
vehicle or in the workshop.
In the vehicle
avoid discharges by battery operation for one
week by minimizing disconnection of the vehicle from the power line.
More time intensive - but better and safer - is to charge the battery
in the workshop
ensuring a full charge over 72 hours according 8.6.1.
12.1.4
If you decide to dismount the battery, measure the open-circuit voltages of the cells
before connecting to the charge.
After 24 hours the open circuit voltage is an indicator of the state of charge of a cell:
Voltages above 2.14 Vpc are equivalent to 100% charge.
Values less than 1.97 Vpc correspond to a residual charge of less than 20% or a
discharge from over 80% of capacity (depth of discharge DOD >80%).
If most of the cells are discharged to that depth, we recommend a charge in
accordance with the Section 8.6.3 “Recharging after deep discharge”.
For assessing the state of health of the cells, measure after 3 days at the end of the battery
charging according to section
Recharging the battery in the workshop
” the
individual cell
voltage during trickle charge. If the cell voltages are not within a window of ± 0.3 Volt, continue the
charge and repeat the measurement after 10 completed days. Rate the cell voltages in
accordance with the “Decision tree for analysis of voltage deviations” in 16 “