Theory of Operation
8
ONePlus UPS User Instruction Manual
If the battery becomes exhausted while maintaining
the load, battery backup terminates and the UPS
output turns off. A low battery warning is sounded
and transmitted via the communications port
approximately two minutes prior to termination of
battery backup. The UPS monitors the line and
provides output when utility power is restored to
normal operating range.
Fig. 1: ONePlus UPS Front View
Output Overload
Protection
During normal operation, electronic output overload
protection is active. If the output is loaded to more
than 105 percent of the UPS rating, battery power to
the UPS is not available. To reset, turn the UPS OFF,
remove some of the load, then turn the UPS ON. (For
GS compliance: The power distribution system for
all models is type TN.)
Input Protector
A grossly overloaded UPS trips the rear panel circuit
breaker. The front panel display reads “c1.” To reset
the circuit breaker, push the button in.
• If the circuit breaker trips repeatedly following
reset, unplug the equipment from the UPS output
receptacles and reset the circuit breaker once
again.
• If operation appears to be normal, check the total
equipment load. Add your equipment to the
output one device at a time. Check the front
panel display after each device is powered ON.
Output ON/OFF Switch
Front Panel Display
