MPS Doc: M359_USER_MANUAL REV G January 17, 2010 Page 17 of 30
5.5.11.
BATT CHARGE [%] Bar-Graph (29).
The Battery Charge Bar Graph indicates the charge level of the battery. 100% signifies
that the battery is fully charged and will support 5 minutes at 2KW, 50% signifies 2.5
minutes at 2KW. Lower loads will result in longer hold-up time. When the Battery
Charger is charging the Battery, the uppermost active segment of the Battery Charge
Bar Graph will blink.
5.6. UPS Response to Input AC Failure
When the input AC voltage is below the minimum level required for proper operation, the
UPS will use the internal Battery to support the AC Output. During this condition the INPUT
FAIL red LED (17) will be on, the ON BATT Warning yellow LED (16) will blink, and five
seconds after the input power has been lost, an audible alarm will start beeping once every
five seconds.
To turn off the audible alarm
, press momentarily on the ALARM OFF Push-button (15).
When the button is pressed, a short beep will sound to indicate compliance.
Note: In M359-1of REV-C (or higher), this button if depressed for more than 10 seconds will set
the Batt Charge Level Indicator to 100% (used during the Manufacturer’s In-Process testing).
Due to the On-line topology of the M359 (see figure 1), the output voltage is always
generated by the DC-to-AC Inverter, regardless of the prime power source. Hence, the
transition between AC Input to Battery Power and backward, is seamless. When monitoring
the output voltage with an oscilloscope, it is impossible to tell when the transition occurs.
When the UPS operates on Battery power, the BATT CHARGE Bar Graph (29) continuously
displays the remaining battery charge level. When the charge in the battery drops below
35%, the LOW BATT Warning yellow LED (14) will start blinking, indicating that the battery
charge level is low and the audible alarm will start emitting two short beeps once every five
seconds. To turn off the audible alarm, press momentarily on the ALARM OFF Push-button
(15). When the button is pressed, a short beep will sound to indicate compliance.
When the Battery Charge Bar Graph reaches 0% (no segments are lit), the UPS will continue
to operate until the actual voltage of the battery will trip the Over Discharge protection circuit
and will shut down the UPS. When the AC Input voltage recovers, the UPS will turn on
automatically.
