RKI Instruments Digester Gas Monitor - Manual (Page 50)

44 • Alarm Indications Digester Gas Monitor Operator’s Manual
NOTE: The Digester Gas Monitor saves the last gas reading taken during the sample
period of a detection cycle. If the gas reading is still above the alarm 1 setpoint at
the end of the sampling period, that gas reading is saved and the alarm 1 circuit
cannot be reset. The reading must fall below the alarm 1 setpoint during the
sampling period of a detection cycle before the alarm 1 circuit can be reset.
Fail Condition
This section describes the indications for a fail condition and suggests responses to a fail
condition.
Fail Condition Indications
The Digester Gas Monitor senses a fail condition for any of the following:
• the detector wiring is disconnected or incorrectly connected;
• the display reading is -10% of full scale or lower;
• the Digester Gas Monitor or one of its detectors is malfunctioning.
When the Digester Gas Monitor senses a fail condition, it alerts you as follows:
• the fail LED turns on;
• the gas reading for the failing channel is replaced by the FAIL message;
• the buzzer sounds a steady tone;
• the common fail relay de-energizes;
• if installed and set to activate for a fail condition, the horn/strobe begins to flash and
sound a pulsing tone when the fail condition begins.
NOTE: The fail alarm has a 30 second delay that is not user adjustable.
Responding to a Fail Condition
This section suggests responses to a fail condition.
1. Verify that the detector wiring is correctly and securely connected.
2. See the troubleshooting guide in “Troubleshooting” on page 79.
Flow Fail Condition
This section describes the indications for a flow fail condition and suggest responses to a
flow fail condition.
Flow Fail Condition Indications
The Digester Gas Monitor senses a flow fail condition when:
• the flow to the sensors falls below 1.6 SCFH.
When the Digester Gas Monitor senses a flow fail condition, it alerts you as follows:
• a 30 second fresh air purge is initiated and the display reads Flow Fail Purge and
counts down from 30 seconds;
• the buzzer sounds a steady tone;
• if installed and set to activate for a fail condition, the horn/strobe is activated;