User's Manual

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3.17 ALARM, STATUS, CONTROLS INTERCONNECT
See Figure 3-27 for interconnect diagram. The AE-27( ) Relay Interface provides alarm,
control and status inputs, and alarm, status and control relay outputs. All output relays
can be disabled or provisioned normally open or normally closed as follows:
Normally open (NO) – relays are normally de-energized and relay contacts are open. When
activated, relays are energized. Relay contacts close, connecting the output to ground.
Normally closed (NC) – relays are normally energized and relay contacts are closed and
grounded. When activated, relays are de-energized. Relay contacts open, presenting an
open (high impedance) to the output.
Rack ALM Return, Pin 49 is a ground point for use with Rack ALM Out. It is a signal
ground (low current) not used for battery voltage or high current ground.