RKI Instruments 65-2398RK - Manual (Page 19)

65-2398RK Combustible Gas Transmitter • 15
NOTE: When a transmitter is first powered up with a new amplifier, the initial output
may be either high or below zero depending on the setting of the zero pot. Be
sure to make arrangements so that this does not cause unwanted alarms.
10. Turn on power to the controller.
11. Turn on the controller and place it into normal operation.
NOTE: When first powered up, the transmitter will enter about a one minute period
when the 4-20 mA output is stabilizing and may be above the controller alarm
points or well below zero momentarily. RKI controllers have a one minute
warmup period when the controller does not display any gas reading or give any
alarm indication. The combustible gas transmitter’s 4-20 mA signal should be
stable by the time the controller’s warmup period is over.
12. Allow the transmitter to warm-up for 5 minutes.
13. Calibrate the transmitter as described in “Calibration” on page 15 of this manual.
Calibration Frequency
Although there is no particular calibration frequency that is correct for all applications, a
calibration frequency of every 6 months is adequate for most infrared combustible gas
transmitter applications. Unless experience in a particular application dictates otherwise,
RKI Instruments, Inc. recommends a calibration frequency of every 6 months.
If an application is not very demanding, for example detection in a clean, temperature
controlled environment where calibration adjustments are minimal at calibration, then a
calibration frequency of every 9 to 12 months is adequate.
If an application is very demanding, for example if the environment is not well controlled,
then more frequent calibration than every 6 months may be necessary.
Calibration
This section describes how to calibrate the combustible gas transmitter. It includes
procedures to prepare for calibration, set the zero reading, set the response reading, and
return to normal operation.
WARNING: The controller is not an active gas monitoring device during the calibration
procedure.
DETECTOR “W” WHT
DETECTOR “G” GREEN
DETECTOR “B” BLK
Table 5:Reconnecting the LEL
Detector to the Amplifier
Amplifier Detector
Terminal Strip
Detector Lead