Communications, Communications interface port, Pin 4 - remote shutdown on battery – Liebert UPSTATION GXT 2U User Manual
Page 21: Ommunications, 4 - r

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COMMUNICATIONS
C
OMMUNICATIONS
I
NTERFACE
P
ORT
The UPStation GXT 2U UPS contains a standard DB-9 serial port female
connector located on the rear of the UPS unit. Several signals are pro-
vided on this port and are assigned as follows:
*Maximum voltage and current on pins 1, 7, 8, and 9 is 60V DC; 10.0 mA.
P
IN
4 - R
EMOTE
S
HUTDOWN
ON
B
ATTERY
1. This pin is functional only when the UPS is in battery mode. If the
UPS is being powered by the utility, Pin 4 will ignore any signal on this
pin.
2. Pin 4 requires a 5-12 VDC signal to shutdown. This normally comes
form the serial port using Liebert’s contact closure cable. It cannot be
used with just a contact closure unless the relay is used to switch a
voltage source. A 5-12 VDC signal for 1.5 seconds or greater is
required to signal a shutdown. Signals for less than 1.5 seconds will
be ignored. After Pin 4 receives a shutdown signal for 1.5 seconds,
the command cannot be canceled.
Pin
Assignment Description
1
Low Battery (open collector)
2
UPS TxD (typical RS-232 levels)
3
UPS RxD (typical RS-232 levels)
4
Remote Shutdown (5-12VDC, 10-24 mA max); battery operation
5
Common
6
Remote Shutdown (short to pin 5); all modes of operation
7
Low Battery (open emitter)
8
Utility Fail (open emitter)
9
Utility Fail (open collector)
Pin Assignment
Collector to Emitter*
5
4
3
2
1
6
7
8
9
(-)
(+)
330 Ohms
Open
Collector
Open
Emitter