Function - NEC 500 UPS User Manual

8. Function

Self-test
The UPS performs a self-test automatically when turned on with the enable switch (by default). Automatic self-test eases
maintenance requirements by eliminating the need for periodic manual self-tests. During the self-test, the UPS briefly operates
the loads on-battery. If the UPS passes the self-test, it returns to on-line operation.
If the UPS fails the self-test it immediately returns to on-line operation and lights the replace battery LED. The loads are not
affected by a failed test. Recharge the battery overnight and perform the self-test again. If the replace battery LED is still on,
replace the battery using the Replacing the Battery procedure.
Automatic Voltage Regulation
A transformer with a winding that can be switched to boost or trim the AC line voltage is used to correct for low or high input
voltage without using the battery continuously.
Boost
AC Line to Boost Boost to AC Line
92 V 2% 96.5 V 2%
Trim
AC Line to Trim Trim to AC Line
108 V 2% 104 V 2%
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