Panasonic Electric Works Nordic AB
MEW01351
Rev: -
Planning Instructions Fire alarm system EBL512 G3, V1.1.x
153
25.1
Charger functions
According to EN54-4, section 5.3.1 b)
:
The charger shall be
designed and rated so that a battery discharged to its final voltage can
be recharged to at least 80% of its rated capacity within 24 hours and
to its rated capacity within another 48 hours
.
25.1.1
Charging
If the EN54-4 section is to be fulfilled, the battery capacity of the
backup batteries is limited to 65 Ah.
However, batteries of larger capacity are possible to use but will not
be recharged within the prescribed time interval, i.e. an EN54
violation.
Batteries of smaller capacity (i.e. < 24 Ah) are not recommended since
the charging current in step 1 (see below) is 2.4 A, which normally is
higher than the recommended maximum charging current for these
batteries. Too high charging current can cause abnormal internal
heating which may damage the batteries.
25.1.2
Battery charging functions:
Battery charging is performed in two steps:
1.
Constant current.
The charging current is constant (fixed)
until the battery / charging voltage reaches 29 V.
2.
Constant voltage.
The charging voltage is reduced from 29 to
something between 26.8 and 28.2 V (depending on the
temperature) and will be constant (fixed) at this level until the
batteries are fully charged.
When the battery is fully charged the stand-by "charging current" is 0-
0.5 A (typical 0.1 A) and the "charging voltage" will stay constant
(fixed) at the "step 2" level, until the batteries have been discharged
and have to be charged again. A new charging cycle will then start.
The duration of "step 1" and "step 2" respectively is depending on the
battery shape when the charging starts.
25.1.3
Security functions
The battery charging will be turned off if the current from the
Rectifier 5037 to the Main board 5010 exceeds 6.3 A. The
battery charging will remain turned off as long as the EBL512
G3 current consumption exceeds 3.3 A. The following fault
message will be shown:
FAULT: Control unit xx high current
consumption
In case of charger out of work the following fault message will
be shown:
FAULT: Charger control unit xx
