User Manual

Model GD-K77D
Operator’s Manual Alarms • 30
Alarm Point. When the target gas concentration reaches or exceeds the alarm point, the
alarm contact is activated. The alarm contact is self-resetting when the gas concentration
falls below the alarm point.
Figure 11: Alarm Operation
Responding to Alarms
This section suggests responses to gas and fail alarms.
Gas Alarm s
Follow your established procedure for an increasing toxic gas condition. When the target
gas concentration reaches or exceeds the alarm point, the alarm contact is activated. The
alarm contact is self-resetting when the gas concentration falls below the alarm point.
Fail Alarms
Set the correct flow rate with the flow adjust valve. If you cannot set the correct flow rate,
check the sample lines for obstructions or kinks. Calibrate the Model GD-K77D. If the fail
condition continues, contact RKI Instruments, Inc. for further instruction.
Interfering Gas
If you suspect gasses other than the target gas as the cause of an alarm, contact RKI
Instruments, Inc.
A lar m contact
(Terminals 7 & 8)
0
A LM1 a l arm p oint
A l ar m LED (A LM1)
A l ar m LED (A LM2)
A l ar m delay t ime
(3 sec)
A l ar m delay t ime
(3 sec)
A lar m contact
(Termi nals 9 & 10)
Time
Gas
Conc entration
A LM2 a l arm p oint