Liebert UPStation-GXT interface

9 pin D-SUB male connector at the UPS

Pin#	Function
1	Low Battery (Optocoupler Collector: +V)
2	UPS TxD
3	UPS RxD
4	Remote ShutDown (+5..12VDC, 10 mA max); on battery operation
5	Common
6	Remote ShutDown (Short to pin 5); any mode operation
7	Low Batery (Optocoupler Emitter: -V)
8	Utility/Mains Fail (Optocoupler Emitter: -V)
9	Utility/Mains Fail (Optocoupler Collector: +V)

Maximum voltage and current on pins 1,7,8,9 shall be 80 VDC, 10.0 mA max