Liebert GXT 2U Power Supply User Manual


 
Communications
20
7.2 PINS 4 & 5 - REMOTE SHUTDOWN ON BATTERY
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.
3. A battery shutdown signal on Pin 4 will NOT cause an immediate
shutdown. A shutdown signal will start a 2-minute shutdown
timer. The timer cannot be stopped. After 2 minutes, the UPS will
shut down.
4. If the utility returns during the 2-minute timer countdown, the
shutdown timer will continue until the end of 2 minutes and the
UPS will turn OFF. The UPS must remain OFF for at least 10
seconds even if AC input power returns before the UPS turns
OFF. This serves to reset and restart the server.
Whether the UPS turns back ON when power is restored depends on
the auto-restart setting: enabled or disabled.
If the auto-restart is disabled, the UPS will not restart after perform-
ing the 2-minute shutdown delay.