RKI Instruments Digester Gas Monitor - Manual (Page 51)

Digester Gas Monitor Operator’s Manual Alarm Indications • 45
• the common fail relay de-energizes;
• the flow to the sensors is stopped;
• After the purge is completed, a sample sequence is initiated. If the low flow condition
recurs during this sample period, the Digester Gas Monitor will stop sampling and wait
for user intervention.
Responding to a Flow Fail Condition
This section suggests responses to a flow fail condition.
1. During the 60 second purge, press and release the reset button to silence the buzzer
and the horn/strobe (if the Fail Silence parameter in the Global Menu is set to CAN
SILENCE FAIL).
2. If 2 detection cycles in a row experience a flow fail, verify that nothing is blocking the
inlet lines.
3. If a flow fail occurs for a second consecutive detection cycle, the Digester Gas Monitor
will wait for user intervention. Press and release the reset button once to silence the
buzzer and once again to reset the LED and the relay. The Digester Gas Monitor will
enter a 60 second standby period and then begin a new detection cycle.
If the cause of the flow fail has been cleared and the flow is normal during the second
detection cycle, a new standby period is started at the end of the detection cycle.
4. See “Troubleshooting” on page 79.
Low DC Power Condition
This section describes the audible and visual indications for a low DC power condition and
suggests responses to a low DC power condition. This condition only occurs when DC
power is used as the primary or a backup power source.
Low DC Power Condition Indications
The Digester Gas Monitor senses a low DC power condition when the DC power source is
18.5 volts or less.
WARNING: While in a low power condition, the Digester Gas Monitor is not an active
gas monitor.
When the Digester Gas Monitor senses a low DC power condition, it alerts you as follows:
• The FAIL LED turns on.
• The fail relay and all other relays are de-energized.
• The message LOW POWER S STANDBY is indicated on the top line of the LCD and
the input voltage is displayed on the bottom line of the LCD.
NOTE: The low DC power alarm cannot be cleared using the reset switch.
When the DC input voltage increases to 19.0 volts, the low DC power alarm is cleared and
the Digester Gas Monitor will begin its warm-up sequence.
Responding to a Low DC Power Condition
• If DC power is the primary power source:
1. For a temporary DC power source, disconnect primary DC power at the Digester