GREEN INSTRUMENTS G36 - Page 15

G36 Oxygen Analyzer
Version 2.11 - March 2022 15
For the Stack Gas Oxygen Analyzer and the EGR Oxygen Analyzer relay functions and
connections are as follows:
Relay No.
Relay function
Terminal Connections
Internal power supply
+ 24 VDC
Terminal 1
Relay 1
Alarm High/Low/
High-High O
2
level
Terminals 2.1-3.1-4.1
(NC-COM-NO)
Inverted
Normally energized
Relay 2
System failure alarm
Terminals 5.2-6.2-7.2
(NC-COM-NO)
Inverted
Normally energized
Relay 3
Auto Back-flushing
Terminals 8.3-9.3-10.3
(NC-COM-NO)
Normally
de-energized
Relay 4
Auto-Calibration
Terminals 11.4-12.4-13.4
(NC-COM-NO)
Normally
de-energized
Internal power supply
– ground
Terminal 14
Alarms
The values for three O2 level alarms (Low, High, and High-High) can be set following
instruction in section 7.2.
The system failure alarm includes a sensor alarm and alarm for open loop of the analog
outputs. If the G36 Oxygen Analyzer is configured with a digital flow switch, the system
failure alarm will also include the flow alarm.
Normally energized
Normally energized means that the relay is energized in the alarm free condition during
operation. The relay will be de-energized when there is an alarm or when the supply volt-
age disappears from the analyzer. Thus, the normally energized relays will give a fault
signal in the event of failure of power to the analyzer.
Normally de-energized
Normally de-energized means that the relay is de-energized in the normal operating con-
dition. For the Inert Gas Oxygen Analyzer, relay 4 (normally de-energized) will be ener-
gized in span calibration condition. For the Stack Gas Oxygen Analyzer or the EGR Ox-
ygen Analyzer, relay 3 or 4 respectively will be energized when the analyzer is back-
flushing or auto calibrating.