Nortec EL11 Operating Instructions Manual page 11

19-Dec-23 Operation Instruction EL11
Charging (section 24V / 5A or 24V / 10A)
- Pre-charge-U
The pre-charging process has been devised for activating and recharging deep-discharged battery sets
with an off-load voltage of more than 0.5VDC. The battery set is charged with a constant voltage of
28.8V until the charging current has increased to 5A respectively 10A. Maximum pre-charging time 12
hours otherwise the charger indicates an error. Starting from an off-load voltage of 25V the pre-charging
step will be skipped.
- Main charge-I
The battery set is charged with a constant current of 5A respectively 10A until the voltage of the battery
set has reached 28.8V.
- Main charge-U
The battery set is charged with a constant voltage of 28.8V until the charging current has decreased to
1A. The main charging process must have finished latest after 34h (functional sector 5A) respectively
22h (functional sector 10A).
Trickle‐charging (section 24 V 1 A)
The trickle-charging is identical for both sectors. The trickle-charging process starts directly after
finishing the main charge process.
The device waits until the off-load voltage has declined to the lower threshold of 25.4V. This phase is
called supervision. The yellow LED "ERHALTUNGSLADUNG" = TRICKLECHARGE is blinking. The
battery set will be charged with a constant current of 1A until the upper threshold 28.2V has been
reached. This phase is called trickle-charge. The yellow LED "ERHALTUNGSLADUNG" = TRICKLE-
CHARGE is illuminated until this value is reached.
Again, the device waits until the lower threshold of 25.4V is reached, after that the trickle charge current
of 1A is started.
This process repeats again and again and guarantees an average status of charge of minimum 50%.
The whole charging process consisting of charge and trickle-charge starts automatically:
- After starting the charging section after pressing the push-button with connected batteries
- After mains failure and return of power
- In the trickle-charge phase if the battery voltage is beneath the lower threshold of 25.4V for more than
60 seconds
© Nortec Electronics 2023 11