APC 412 kVA User Manual

Page of 64
C
HAPTER 
4:  I
NSTALLATION
 
 
24 
 
 
 
 
 
 
 
 
 
Option 1: Internally Powered                     
(with Jumper Cable) 
 
 
 
 
Option 2: Externally Powered                      
(no Jumper Cable) 
 
 
 
12.  If required, connect the Remote Emergency Power Off 

 
(REPO) circuit. Check national and local codes before wiring.  
The output power can be disabled in an emergency by  
closing a switch connected to the REPO. You must physically 
reset the system enable switch on the front of the UPS to 
restart the unit. 
 
 
 
The REPO circuit is considered a Class 2  
 (UL and CSA standards) and SELV  
 (IEC standard) circuit. 
 
Class 2 Circuit:  Used in North America by UL 
and CSA. It is defined in the National Electrical 
Code (NFPA 70, Article 725) and in the 
Canadian Electrical Code (C22.1, Section 16). 
 
SELV Circuit:  Used in Europe by IEC; acronym 
for “safety extra low voltage.” A SELV circuit is 
isolated from primary circuitry through an 
isolating transformer and designed so that under 
normal conditions, the voltage is limited to  
42.4 V peak or 60 V dc 
 
Both Class 2 and SELV circuits must be isolated 
from all primary circuitry. Do not connect any 
circuit to the REPO terminal block unless it  
can be confirmed that the circuit is SELV or 
Class 2. If there is a question, use a contact 
closure switch. 
 
Use one of the following cable types to connect 
the UPS to the EPO switch: 
CL2: Class 2 cable for general use. 
CL2P: Plenum cable for use in ducts, plenums, 
and other spaces used for environmental air. 
CL2R: Riser cable for use in a vertical run in a 
shaft of from floor to floor. 
CLEX: Limited use cable for use in dwellings  
and for use in raceways. 
For installation in Canada: Use only CSA 
Certified, type ELC (extra-low voltage  
control cable). 
 
Wiring by a qualified electrician is required. 
 
Connect using Option 1 if internally powered. 
 
Connect using Option 2 if externally powered. 
 
 
 
24 
Vdc