RKI Instruments Digester Gas Monitor - Manual (Page 49)

Digester Gas Monitor Operator’s Manual Alarm Indications • 43
begin to flash indicating the alarm condition has been acknowledged. You cannot de-
energize the alarm 2 relays until the gas reading falls below the alarm 2 setpoint.
3. Alarms are factory set as latching. After the gas reading falls below the alarm 2
setpoint during a detection cycle, press and release the reset switch to reset the alarm
circuit. Resetting the alarm circuit silences the buzzer (if the alarm has not been
acknowledged) turns off the alarm 2 LED, resets the display for the channel(s) in
alarm, turns off the horn/strobe if it is installed and set to activate for alarm 2 only, and
de-energizes the channel alarm 2 relays.
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.
Alarm 3 Condition
This section describes the indications for an alarm 3 condition and suggests responses to
an alarm 3 condition.
NOTE: The factory set configuration of the Digester Gas Monitor does not assign
channel relay contacts to the alarm 3 condition.
Alarm 3 Condition Indications
When the gas reading of an active channel reaches the alarm 3 setpoint, the Digester Gas
Monitor senses an alarm 3 condition. The Digester Gas Monitor alerts you to an alarm 3
condition as follows:
• the alarm 3 LED turns on
• the gas reading during an alarm 3 condition continues to flash and alternates with the
ALM 1,2,3 message
• the buzzer sounds a pulsing tone
• if installed and set to activate for alarm 1 and alarm 2, the horn/strobe continues to
flash and sound a pulsing tone
• if set to activate for alarm 3 only, the horn/strobe begins to flash and sound a pulsing
tone when an alarm 3 condition begins
Responding to an Alarm 3 Condition
This section suggests responses to an alarm 3 condition.
1. Follow your established procedure for a high-level combustible or toxic gas condition,
or an increasing oxygen condition.
2. An alarm condition can be acknowledged at any point during the detection cycle or
during Standby Mode. To acknowledge the alarm condition and silence the buzzer
while in an alarm 3 condition, press and release the reset switch. The ALARM 3 LED
will begin to flash indicating the alarm condition has been acknowledged.
3. Alarms are factory set as latching. After the gas reading falls below the alarm 3
setpoint during a detection cycle, press and release the reset switch to reset the alarm
circuit. Resetting the alarm circuit silences the buzzer (if the alarm has not been
acknowledged) and turns off the ALARM 3 LED.