External Connection
990-4049
Installation Guide APC Silcon 240-320kW 480V UPS 25
Auxiliary contacts on the main switches transmit 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 (also used with battery monitoring).
“Battery operation” and “Common fault” are the two main status SII-board relay signals.
4.2.1 Connecting the System Integration Interface Board (SII-board)
SII Board
Terminal rows: X003 and X004 (auxiliary contacts)
When switching Q001, Q002, Q010, Battery Breaker 1 or Battery Breaker 2 from “ON or 1” to
“OFF or 0”, the auxiliary contact must open BEFORE the corresponding main contacts are
opened. When switching Q001, Q002, Q010, Battery Breaker 1 or Battery Breaker 2 the
opposite way from “OFF or 0” to “ON or 1”, the auxiliary contact has to close with a maximum
delay of 0.5 seconds from the time the corresponding main contacts are closed.
• This type of auxiliary contact is called a “late make” contact. (This also means that
it will “break early” when activated in opposite direction)
NOTICE!
If the UPS is equipped with an Emergency Power Off (EPO) facility all input sources must be
equipped with disconnecting devices.
X004 X003
X012
X005
X001
S002
S001