21
500 Interpreting the Front Panel LEDs
501 Line and Load Level LEDs
During normal operation, the UPS rectifies the AC input and uses it to charge the batteries and feed the inverter.
The Line (~) LED shown below is on. In this mode, the five front panel LEDs shown in the drawing show the
percentage of the rated UPS power that your equipment is using. The more power your equipment requires, the
more LEDs are lit. See the drawing below. If the Line (~) LED flashes and the unit switches to battery
power or bypass, the AC input voltage is too low or too high.
502 Battery Power (Inverter) and Battery Charge LEDs
When the UPS runs on battery backup power (inverter), the Battery and Inverter LEDs are on as shown. This
happens during a power outage or when AC input (utility) power is not acceptable.
When the UPS runs on battery power, the five LEDs shown in the drawing show the amount of battery charge
that is left. As the UPS runs on battery power, the amount of charge (and the amount of time the UPS can
continue running on battery) will decrease, and the LEDs will begin to go out, starting with the bottom LED.
See the drawing below. If the Battery LED starts flashing, battery voltage is low (below 240 VDC).
0-35%
35-55% 55-75% 75-95% 95-105% Overload
Figure 16
0-35%
35-55%
55-75%
75-95%
95-105%
Figure 17
