25-75 kW
User's and Installation Guide
71
6.7UsingtheRemoteEmergencyPower-offswitch
A UPS emergency power-off is initiated by the EPO pushbutton switch. In an emergency, you can use this
switch to control the UPS output. The EPO switch de-energizes the critical load and powers down the UPS
immediately, without asking for verification. The UPS, including Bypass, remains off until restarted.
CAUTION
AllpowertothecriticalloadislostwhentheEPOswitchisactivatedinthefollowingstep.Youshouldusethis
featureonlywhenyouwanttode-energizethecriticalload.
NOTE
ThefollowinginstructionsarefortheEatonCorporation-suppliedEPOswitch.Ifacustomersupplied
EPOswitchisused,itmaynotactivateinthesamemanner;refertotheoperatinginstructionsprovidedwiththe
switch.
DANGER
DonotattempttorestartthesystemafterLoadOffuntilthecauseoftheshutdownhasbeenidentifiedand
cleared.
6.8 Transfer the UPS from Double Conversion Mode to Maintenance Bypass Mode
The operation of the internal MBS is allowed for a trained person only who is familiar with the UPS behavior
and functions. The full UPS wiring diagram with a MBS switch is presented in the installation instructions.
NOTE
The integral MBS and Static Bypass need to supplied by the same source.
To use the EPO switch:
1. Press the EPO pushbutton switch.
The input, output, and bypass backfeed relays open, the battery breaker or disconnect is tripped, and the
power module is turned off immediately, without asking for verification.
2. To restart the UPS after using the EPO pushbutton, reset the EPO switch and then follow the procedure in
Chapter 6.4.1 Starting the UPS system in Double Conversion Mode or Chapter 6.4.2 Starting the UPS system
in Bypass Mode.