External Connection

990-4050

Installation Guide APC Silcon 10-40kW 400V UPS 17

4.2 System Integration Interface

System Integration Interface (SII) is the control link between UPS and system main switches
as shown in above diagram. The purpose of the SII is to ensure correct operation of switches
without losing system output power.
Auxiliary contacts on the main switches transmit the SII board inputs. Lamps on Service
Bypass Panel and Battery Breaker Box/Battery Cabinet indicate “green light” for operation of
output switches.
SII board also integrates input facilities for emergency shut-down and temperature
compensation of charge voltage for external battery (use with battery monitor). “Battery
operation” and “Common fault” are two main SII board status relay signals.
NOTICE!
Consistent use of designations (Q001, Q002, Q003, H002, H003) in diagrams simplifies
information exchange.