C750 & C750R User
Manual Page 23
3.4 POWER CABLES CONNECTION
This chapter introduces how to wire AC IN/OUT cables to UPS in different mode, and UPS connecting with EBM/MBP.
3.4.1 INPUT /OUTPUT WIRING SPECIFICATION
Before wring the UPS upstream breaker a backfeed contactor should be installed to avoid power backfeed to the
UPS a ‘backfeed voltage danger’ warning label should be added on the backfeed contactor or device. Before
operating the UPS input be isolated and measured to check correct voltages and polarity. Backfeed contactor
current rating should be larger than that off the UPS input current rating.
Below figures show the wiring system of UPS input. Always adhear to the local wireing regulations and requirements
for backfeed contactors
Single phase input system:
Three phase input system:
Danger!
The rated current of the utility power contactor must be greater than the UPS input current to avoid damage.
