65-2380 Molecular Property Spectrometer Combustible Gas Detector Operator’s Manual Part Number: 71-0595 Revision: P2 Released: 10/14/22 RKI Instruments, Inc. www.rkiinstruments.
WARNING Read and understand this instruction manual before operating transmitter. Improper use of the transmitter could result in bodily harm or death. Periodic calibration and maintenance of the transmitter is essential for proper operation and correct readings. Please calibrate and maintain this transmitter regularly! Frequency of calibration depends upon the type of use you have and the sensor types.
Product Warranty RKI Instruments, Inc. warrants gas alarm equipment sold by us to be free from defects in materials, workmanship, and performance for a period of one year from date of shipment from RKI Instruments, Inc. Any parts found defective within that period will be repaired or replaced, at our option, free of charge.
Table of Contents Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 Applications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Overview This manual describes the 65-2380 MPS combustible gas detector. This manual also describes how to install, start up, maintain, and calibrate the detector when used with a gas monitoring controller. A parts list at the end of this manual lists replacement parts and accessories for the combustible gas detector. Specifications Table 1 specifies the detection ranges and accuracy for each target gas the MPS sensor can detect.
Table 2: Specifications Area Classification Explosion-proof for Class I, Groups B, C, and D Operating Temperature Range -20ºC to +50ºC (-4ºF to +122ºF) Humidity Range 0 - 100% RH (non-condensing) Pressure Range 80 - 120 kPa Sampling Method Diffusion Response Time T90 in 25 seconds Dead Bands • Methane (CH4): 3% LEL • All other gases: 5% LEL WARNING: When using the 65-2380, you must follow the instructions and warnings in this manual to assure proper and safe operation of the 65-2380 and to mi
Description The 65-2380 combustible gas transmitter utilizes a Molecular Property Spectrometer (MPS) sensor. The MPS sensor is immune to poisons, can be used in high humidity, and does not require calibration as often as catalytic combustible sensors. It also responds accurately to 14 different combustible gases. This section describes the components of the combustible gas transmitter. The transmitter is a 4 20 mA type detector head. It consists of the combustible gas detector, amplifier, and junction box.
MPS Detector The MPS LEL detector is made up of the MPS combustible gas LEL detector housed and encapsulated in a pipe nipple. The pipe nipple has 3/4 NPT threads on each end and a 1-1/4 inch hex that allows removal or installation of the detector with a wrench. A porous flame arrestor coated with a hydrophobic film that repels liquids is on one end of the detector and allows sample gas to enter the detector. Four color coded leads, red, white, green, and black, extend from the other end of the detector.
Controller Terminal Strip The controller terminal strip is a three position plug-in style terminal strip located near the top of the amplifier. Use the controller terminal strip to wire the combustible gas transmitter to a controller. Detector Terminal Strip The detector terminal strip is a four position plug-in style terminal strip located below the controller terminal strip. Use the detector terminal strip to connect the MPS LEL detector to the amplifier.
Installation This section describes procedures to mount the combustible gas transmitter in the monitoring environment and wire the transmitter to a controller. Mounting the Combustible Gas Transmitter 1. Select a mounting site that is representative of the monitoring environment. Consider the following when you select the mounting site. • Select a site where the transmitter is not likely to be bumped or disturbed.
Wiring the Combustible Gas Detector to a Controller WARNING: Always verify that the power to the controller is off before you make wiring connections. 1. Turn off the controller. 2. Turn off or unplug power to the controller. 3. Remove the junction box cover. 4. The detector leads are factory wired. Verify that the detector leads are wired to the amplifier’s detector terminal strip as shown in Figure 11. 5.
11. Connect the wires to the applicable detector/transmitter terminal strip at the controller as shown in Figure 11. + 24 VDC 4 - 20 mA In (S) - (DC G round) Cable S hield Controller or Recording Device J-Box S R W G L EL B PWR / SI G Amplifier (Transmitter) Black Green W hite Red Detector W ires MPS LEL Detector Figure 4: Wiring the Combustible Gas Transmitter to a Controller 12.
Start Up This section describes procedures to start up the combustible gas transmitter and place the transmitter into normal operation. NOTE: The detector must be started up in fresh air. 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 power to the controller. 4. Turn on the controller. 5.
6. Screw the regulator into the zero air calibration cylinder. 7. Use the calibration kit sample tubing to connect the regulator to the calibration cup. 8. Turn the regulator’s on/off knob counterclockwise to open it. Gas will begin to flow. 9. Allow the gas to flow for one minute. 10. Verify a voltmeter reading of 100 mV (±2 mV). 11. If necessary, use a small flat-blade screwdriver to adjust the zero pot until the voltmeter reading is 100 mV (±2 mV). 12.
Troubleshooting The troubleshooting guide describes symptoms, probable causes, and recommended action for problems you may encounter with the combustible gas transmitter. NOTE: This troubleshooting guide describes transmitter problems only. See the controller operator’s manual for problems you may encounter with the controller. Table 3: Troubleshooting the Combustible Gas Transmitter Condition Symptom(s) Probable Causes Recommended Action Fail Condition • Controller indicates a fail condition.
Replacing the MPS LEL Detector 1. Turn off the controller. 2. Turn off or unplug power to the controller. 3. Remove the junction box cover. 4. Remove the detector terminal strip from its socket. 5. Disconnect the detector leads from the detector terminal strip. Note the position of the colorcoded leads as you remove them. 6. Unscrew the detector from the junction box. 7.
Replacing the Amplifier 1. Turn off the controller. 2. Turn off or unplug power to the controller. 3. Remove the junction box cover. 4. Unplug the detector terminal strip and controller terminal strip from their sockets. You may leave the wires connected to the terminal strips. 5. Unscrew and remove the screw with the flat and lock washers that secures the amplifier to the junction box. 6. Remove the old amplifier. 7. Place the new amplifier in the same position as the old amplifier.
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. 12. Allow the transmitter to warm-up for 5 minutes. 13. Calibrate the transmitter as described in “Calibration” on page 18 of this manual.
Materials The following items are required for detector calibration: • a CH4 calibration cylinder (in a background of real air which contains argon and CO2) • a 0.5 LPM fixed flow regulator with an on/off knob • a calibration cup for the detector • a short piece of sample tubing to connect the regulator to the calibration cup • a voltmeter Preparing for Calibration 1. Unscrew and remove the junction box cover. 2. Set a voltmeter to measure in the millivolt (mV) range. 3.
5. Allow the gas to flow for one minute and verify a reading of 100 mV (±2 mV). If necessary, use the zero pot on the amplifier to adjust the reading to 100 mV (±2 mV). 6. Turn the regulator’s on/off knob clockwise to close the regulator. 7. Unscrew the regulator from the zero air calibration cylinder. 8. Leave the sample tubing connected to the regulator and the calibration cup. Setting the Response Reading 1. Ensure that only an MPS-specific methane calibration cylinder is in use. 2.
Parts List Table 7 lists replacement parts and accessories for the combustible gas transmitter. Table 7: Parts List Part Number Description 06-1248RK Sample tubing (3/16 in. x 5/16 in.
