APC SILCON 990-4053 - Manual (Page 15)

External Connection
990-4053
Installation Guide APC Silcon 480kW 400V UPS 15
External Control Cables
External multicore cable is equipped with 15-pin SUB-D plug at either end. Connect pin 1 to
pin 1, and pin 2 to pin 2 etc. up to pin 15 - with the exception of pin 8, which is not to be
connected.
Shield is connected to plug cover at both ends.
Terminals X020 and X021 for control cables located on parallel board. Connect X020 in UPS1
to X021 in UPS2, and connect X020 in UPS2 to X021 in UPS3 etc. Connect X020 in last UPS
to X021 in UPS1.
Cable is delivered with the UPS.
Power Cables
To optimize load-sharing in parallel operation, external power circuits must be “symmetrical”:
Power input and output cables to have same length and identical cross-sections.
to other parallel units
UPS 1 UPS 2 UPS 3
X020:15-pin SUB-D female
X021:15-pin SUB-D female
Parallel Board
External multicore cable with 14 wires + shield