APC Rack Automatic Transfer Switch, 12A, 230V SU043 User Manual

You can use a remotely operated Emergency Power Off (

EPO

) 

switch to turn off the 

UPS

 and disconnect power to the 

equipment load. When you turn off the 

UPS

 through the 

Emergency Power Off system, it will turn off immediately 
without switching to battery operation. 

1. Use the 

EPO

 connector.

2. Use a normally-open contact to connect the +24 terminal 

to the 

IN

 terminal. 

3. Wire the external blue four-pin female connector to the 

emergency power off system. 

The 

EPO

 interface is a Safety Extra Low Voltage 

(

SELV

) circuit. Connect it only to other 

SELV

 

circuits.

The 

EPO

 interface monitors circuits that have no 

determined voltage potential. Such closure 
circuits may be provided by a switch or relay 
properly isolated from the utility. To avoid 
damage to the Redundant Switch, do not connect 
the 

EPO

 interface to any circuit other than a 

closure type circuit.