RKI Instruments 65-2390RK - Manual (Page 11)

65-2390RK Combustible Gas Transmitter • 7
Start Up
This section describes procedures to start up the combustible gas transmitter and place the
transmitter into normal operation.
Introducing Incoming Power
1. Complete the installation procedures described earlier in this manual.
2. Verify that the power wiring to the controller is correct and secure. Refer to the
controller operator’s manual.
3. Turn on or plug in power to the controller, then place the controller’s power switch in
the ON position.
4. Verify that the controller is on and operating properly. Refer to the controller
operator’s manual.
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.
CAUTION: Allow the detector to warm up for 5 minutes before you continue with the next
section, “Setting the Zero Signal”.
Setting the Zero Signal
CAUTION: If you suspect the presence of combustible gas in the monitoring environment, use
the calibration kit and the zero air calibration cylinder to introduce “fresh air” to the
detector and verify an accurate zero setting.
1. Verify that the transmitter is in a fresh air environment (environment known to be free
of combustible and toxic gases and of normal oxygen content, 20.9%).
2. Unscrew and remove the junction box cover from the junction box.
3. Set a voltmeter to measure in the millivolt (mV) range.
4. Plug the voltmeter leads into the test points on the amplifier. Plug the positive lead
into the test point labeled TP+; plug the negative lead into the test point labeled TP-.
5. Verify a voltmeter reading of 100 mV (±2 mV).
6. If necessary, use a flat-blade screwdriver to adjust the zero potentiometer until the
voltmeter reading is 100 mV (±2 mV).
7. Secure the junction box cover to the junction box.