MGS-250 Manual
26 6490-9000
Revision
4
3.4. Wiring the Digital Alarm Output Relay
An alarm setpoint may be programmed from the front panel of the
MGS-250. When the the sensed gas level exceeds the alarm setpoint,
the MGS-250 enters the alarm state. An on-board relay is tied to the
alarm state, so you may activate (or deactivate) external equipment
based on the MGS-250’s current alarm status.
Figure 11. Sample Relay Output Wiring
NOTE:
The relay can be programed to be failsafe (normally
energized). By default, the relay is set to be normally de-
energized. This can be set using parameter P-06.
Make relay connections (NO, NC, or both) using 18 to 20 AWG wires to
terminal block positions 10, 11, and 12 (see Figure 11), noting normally
open, normally closed, and common connectors per Table 7.
Table 7: Relay Output Terminal Block Connections
Function
Pin
Wiring Termination
Relay (Alarm)
Output
10
Relay NC contact
11
Relay common contact
12
Relay NO contact
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0
5
10
15
20
25
30
