APC RS 550 Unit sensitivity, System Faults, Low sensitivity Medium sensitivity High sensitivity

Unit sensitivity

Adjust the sensitivity of the UPS to control when it will switch to battery power; the higher the sensitivity, the more often the unit will switch to battery power.

1.Ensure the unit is connected to utility power, but is OFF.

2.Press and hold the POWER button for six seconds. The LOAD CAPACITY bar will flash on and off, indicating that the unit is in programming mode.

3.Press POWER again to rotate through the menu options. Stop at selected sensitivity. The unit will beep to confirm the selection.

Low sensitivity Medium sensitivity High sensitivity

156-288 Vac

Input voltage is extremely low or high. (Not recommended for computer loads.)

176-282 Vac

The Back-UPS frequently switches to battery power.

176-276 Vac The connected equipment is sensitive to voltage fluctuations.

Warnings and System Faults

Warnings

Press DISPLAY to scroll through the display screens.

Warning 1

Warning 2

System Faults

ON LINE overload condition,	Warning 3
indicated by the illuminated ON
LINE icon, and the flashing
overload icon.
Backup battery (ON BATT)	Warning 4
overload condition. This is
indicated by the flashing overload
icon.

In ON LINE mode, and there is a bad battery, indicated by the flashing icon.

The battery charge is low, and the Battery Charge indicator bar is flashing.

The unit will display the fault messages. Contact APC Technical Support for additional support.

•F01 - On-Battery Overload

•F02 - On-Battery Output Short

•F03 - On-Battery Xcap Overload

•F04 - Clamp Short

•F05 - Charge Fault

•F06 - Relay Welding

•F07 - Temperature

•F08 - Fan Fault

•F09 - Internal Fault

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4 Back-UPS® RS Installation and Operation