Possible cause:
a)ON button not pushed.
b)UPS not connected to power supply.
C)UPS input circuit breaker tripped.
d)Very low or no utility voltage.
e)Battery not connected properly.
Solution: 1)Press the ON button once to power the UPS and the equipment.
2)Check that the power cable from the UPS to the utility power supply is securely connected.
3)Reduce the load on the UPS by unplugging equipment and resetting the circuit breaker (on the back of UPS) by pressing the plunger in.
4)Check the AC power supply to the UPS by plugging in a table lamp. If the light is very dim, have the utility voltage checked.
5)Check that the battery connector is fully engaged.