20
IMPORTANT!
When the power is turned on, the ALARM indicator always
lights up. Only after 5-10 seconds the device goes into normal operation mode.
3.9.2 Battery charging
When 230 VAC external power supply is available, it will power the switch and
at the same time charge the battery. Charging is implemented in two stages.
First, the battery is charged by direct current (CC=1A). With the increase in
battery power, battery voltage increases too. As soon as it reaches 27V,
charging converts to direct voltage (CV=27V). In this mode voltage gets stable
and current drops with the increase in battery power. This approach ensures
faster and more effective battery charging.
Figure 3.9.2
– Dependence of direct current and voltage on the battery power.
3.9.3 Battery discharge
In case of backup power supply, battery voltage drops from 27 V to the nominal
24 V, then the battery discharges gradually. At this stage the battery releases
most of its power.
