Output Interface (Remote Alarms) Boards (4590044E); Alarm Outputs; Remote Control Inputs - Liebert 7400 Series User Manual

Chapter 4 - Optional equipment

Output Interface (Remote Alarms) Boards (4590044E)

Output Interface (Remote Alarms) Boards (4590044E)
4.3
4.3.1

Alarm outputs

4.3.2

Remote control inputs

4-6
Issue 2
(02/98)
6310018a.02.doc
One remote alarm board, shown in figure 4-3, enables the alarm signals
generated within the UPS to be connected by means of volt-free change-
over relay contacts to a remote monitoring device. The board can be
fitted on the bottom of the UPS cabinet door, together with the AS400
Interface Board.
Note: When using the contacts for remote alarm annunciation, the power
supply for the remote indicators must be provided from an external
power source. Under no circumstances should the UPS internal low
voltage supplies be used for this purpose.
The board has facilities to accept two remote control inputs, as shown in
figure 4-3. One remote input allows the inverter to be shut down
(transferring the load to the bypass supply) and the other enables the
inverter synchronisation feature to be inhibited. The inverter
synchronisation inhibit feature is most often used if the UPS is powered
from a standby generator when the input mains supply fails and the
generator frequency is unstable.
The external control signals (12V dc or ac) should be connected to
terminal block M2 as shown. Once again, the voltage applied to these
terminals must be generated by an external power source and not taken
from the UPS internal low voltage supplies.
7400 Series UPS User Manual
Single Module and One plus One Systems