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ENMET
Corporation
ISA-40 Oxygen Monitor
6
3.2.2 Remote Sensor Assembly Wiring
See Figure 4 for location of terminal blocks and optional intrinsic safety barrier.
Sensor assemblies with intrinsic safety barriers cannot have an audio alarm.
Table 2: Remote Sensor Assembly Wiring
(without Intrinsic Safety Barrier)
Channel
Signal
Control Unit Connection
Sensor Connection
1
Audio Alarm (–)
TB3 – 1
TBS – 1
1
Audio Alarm (+)
TB1 – 1 Horn
TBS – 2
1
Oxygen Cell (–)
TB1 – 1 O2 –
TBS – 3
1
Oxygen Cell (+)
TB1 – 1 O2 +
TBS – 4
2
Audio Alarm (–)
TB3 – 2
TBS – 1
2
Audio Alarm (+)
TB1 – 2 Horn
TBS – 2
2
Oxygen Cell (–)
TB1 – 2 O2 –
TBS – 3
2
Oxygen Cell (+)
TB1 – 2 O2 +
TBS – 4
3
Audio Alarm (–)
TB4 – 1
TBS – 1
3
Audio Alarm (+)
TB2 – 3 Horn
TBS – 2
3
Oxygen Cell (–)
TB2 – 3 O2 –
TBS – 3
3
Oxygen Cell (+)
TB2 – 3 O2 +
TBS – 4
4
Audio Alarm (–)
TB4 – 2
TBS – 1
4
Audio Alarm (+)
TB2 – 4 Horn
TBS – 2
4
Oxygen Cell (–)
TB2 – 4 O2 –
TBS – 3
4
Oxygen Cell (+)
TB2 – 4 O2 +
TBS – 4
Table 2A: Remote Sensor Assembly Wiring
(with Intrinsic Safety Barrier)
Channel
Signal
Control Unit Connection
Sensor Connection
1
Oxygen Cell (–)
IS1 – 2
TBS – 3
1
Oxygen Cell (+)
IS1 – 3
TBS – 4
2
Oxygen Cell (–)
IS2 – 2
TBS – 3
2
Oxygen Cell (+)
IS2 – 3
TBS – 4
3
Oxygen Cell (–)
IS3 – 2
TBS – 3
3
Oxygen Cell (+)
IS3 – 3
TBS – 4
4
Oxygen Cell (–)
IS4 – 2
TBS – 3
4
Oxygen Cell (+)
IS4 – 3
TBS – 4
N
OTE
:
These sensor assemblies cannot have an audio alarm.