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Installation, commissioning and operating instructions for valve-regulated stationary lead-acid batteries
7140203153 V1.4 (09.2018)
Installation, commissioning and operating instructions for valve-regulated stationary lead-acid batteries
7140203153 V1.4 (09.2018)
10 Troubleshooting
If malfunctions occur in the battery or charger, contact customer service immediately.
Measured data as described in Chap. 8.1 simplifies fault detection and elimination.
A service contract with us facilitates the timely detection of faults.
11 Required ventilation for hydrogen generated by batteries
Compliance with VDE 0510 Part 2 or IEC 62485-2 is required to ensure safe ventilation and prevent dangerous
mixtures of hydrogen and oxygen gases (hydrogen approx. 4 %).
Two values form the basis of the equation: the maximum permissible hydrogen concentration in the air is 4 %
and the safety factor is 5. The equation can be derived accordingly:
(Attenuation factor at maximum permissible hydrogen concentration)
(Quantiy of accumulated hydrogen per actual Ah capacity)
(safety factor)
This results in the total equation for the necessary ventilation in [in m
3
/h]:
Q
air
= 0.05 x n x I
gas
x C
N
x 10
–3
I
gas
= I
float
× f
g
× f
s
resp. I
gas
= I
boost
× f
g
× f
s
Q
air
= Necessary ventilation/air flow rate [in m
3
/h]
n = Number of cells
I
float
= Proportion of charge current in mA/Ah used for water dissociation on float charge per 1 Ah nominal
capacity of the battery. = 1 mA/Ah
I
boost
= Proportion of charge current in mA/Ah used for water dissociation on boost charge per 1 Ah nominal
capacity of the battery. = 8 mA/Ah
C
N
= Nominal capacity of the battery (C
10
capacity).
f
g
= Gas emissions factor. Proportion of the charge current responsible for hydrogen accumulation. = 0.2
f
s
= Safety factor which includes the potential for faults resulting from a damaged cell (possible short circuit)
and battery aging. = 5
Example 1:
A battery with 2 x 60 V (60 V nominal voltage), 4 OPzV 200 (200 Ah) is equivalent to 2 x 30 cells. The battery
is on float charge at 2.25 V per cell.
C
N
= Nominal capacity of the battery = 200 Ah
n
= Number of cells = 2 x 30 cells
f
g
= Gas emissions factor = 0.2
f
s
= Safety factor = 5
I
float
= 1 mA/Ah
Cell numer
Case A
Case B
Case C
1
1.84
1.84
1.79
2
1.83
1.86
1.80
3
1.83
1.87
1.81
4
1.84
1.87
1.80
5
1.84
1.86
1.81
6
1.85
1.86
1.79
7
1.69
1.87
1.78
8
1.84
1.86
1.80
9
1.83
1.59
1.81
10
1.85
1.84
1.81
11
1.84
1.85
1.80
12
1.84
1.85
1.79
13
1.85
1.85
1.79
Battery voltage
23.77 V
23.87 V
23.38 V
Tab 9-2: Measured cell voltages and total voltage after 95% of the discharge time has elapsed
Case A: a „weak cell,“ passed capacity test, battery okay
Case B: a faulty cell, failed capacity test, battery not okay
Case C: all cells okay, failed capacity test, battery not okay.
The battery must be charged immediately following the capacity test.
The measured capacity C (Ah) at the average start temperature
is calculated as a product of the discharge
current (in A) and the discharge time (in hours).
As the battery capacity is dependent on the temperature, the measured battery capacity needs to adjusted for
temperature.
At temperatures higher than 20 °C nominal temperature, the battery capacity increases whereas the capacity
decreases at lower temperatures. If the average start temperature
deviates 20 °C from the reference tempe-
rature, the capacity must be corrected.
The start temperature is used to carry out the temperature correction in accordance with the standard DIN EN
60896-21 using the equation [1]:
C
a
= C [1]
1 +
(
- 20 °C)
C = measured capacity
= correction factor (with
= 0.006 for discharges >3 h and
= 0,01 for discharges ≤3 h)
= start temperature
C
a
= corrected capacity
According to the DIN EN 60896-21 standard, the battery has passed the capacity test when 95 % of the requi-
red power is attained in the first capacity test. After the 5th discharge, 100 % of the required power must be
attained.
After discharging, a log must be made
(see Inspection record)
.
Attention!
When handling batteries (e.g. performing capacity tests) you must observe the safety require-
ments in accordance with IEC 62485-2 (insulated tools, protective eyewear, protective
clothing, gloves, ventilation, etc.)!
