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Reference Manual 00809-0100-4303, Rev AB November 2020 ™ Net Safety XChem Electrochemical Sensors...
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All sales are governed by Emerson's terms and conditions, which are available upon request.
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warranty clause shall be borne by Buyer unless accepted in writing by Seller. Goods repaired and parts replaced by Seller during the warranty period shall be in warranty for the remainder of the original warranty period or 90 days, whichever is longer.
Introduction Models covered Emerson has designed the ST3 XChem electrochemical toxic gas sensors for use with the Net Safety Millennium II Transmitter (models M21, M22, or M2B). This sensor is both versatile and reliable, for fast, accurate, and continuous monitoring of gases in extreme environments.
Introduction Reference Manual November 2020 00809-0100-4303 Important Ship all equipment prepaid. Emerson will not accept collect shipments. Product recycling/disposal Consider recycling equipment and packaging. Dispose of the product and packaging in accordance with local and national legislations and regulations. Emerson.com/FlameGasDetection...
(jet lube, etc.) to the threading of the ¾-in. female national pipe thread (FNPT) conduit entry of the enclosure as well as the threading on the sensor ¾-in. male national pipe thread (MNPT) fitting. This aids in protecting the enclosures from water. After Emerson.com/FlameGasDetection...
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Always mount the sensor vertically such that its mouth is pointed in the downward position as shown in Figure 2-2 Figure 2-3. Figure 2-2: Sensor Mounted to a Net Safety Millennium II Transmitter A. ¾-in. national pipe thread (NPT) B. ATEX locking collar C. Sensor pointing downwards D. Sensor mouth Net Safety ST3...
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Install Reference Manual November 2020 00809-0100-4303 Figure 2-3: Sensor Mounted to Net Safety Millennium II Basic Transmitter and Junction Box A. ¾-in. NPT B. ATEX locking collar C. Sensor mouth D. Sensor pointing downwards Emerson.com/FlameGasDetection...
2.6.3 Install to transmitter or junction box Emerson supplies the Net Safety ST3 with a ¾-in. national pipe thread (NPT) male conduit connection. Mount the sensor directly to an available ¾-in. NPT conduit entry on a Net Safety Millennium II Transmitter or remotely using a certified junction box.
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3. Connect the sensor wires to the Net Safety Millennium II Transmitter or junction box as per the appropriate transmitter or junction box manual. Figure 2-7 outlines the connections to a Net Safety M21 Millennium II Transmitter. Table 2-3 outlines the wire colors and their purpose. Emerson.com/FlameGasDetection...
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D. Channel #2 4-20 mA signal E. Earth ground F. White wire G. Red wire H. Blue wire I. Black wire J. M2 transmitter terminal board K. Channel 2 sensor terminals L. Channel 1 sensor terminals M. Sensor Net Safety ST3...
Calibration Note Power up the Net Safety ST3 sensor for at least 24 hours before completing the first calibration. Although Emerson calibrated the sensor at the factory, this calibration may have been disrupted after shipment, and calibration after installation is necessary to ensure performance.
The warm-up time for the Net Safety ST3 sensor is typically between 30 and 90 seconds depending on the sensor type; the Net Safety ST341 oxygen sensor could take up to an hour to warm up.
Contact Net Safety for replacement sensor modules. Sensor communication The Net Safety ST3 sensor uses a proprietary protocol to communicate with the Net Safety Millennium II series of transmitters. Never connect this sensor to any device other than the Net Safety Millennium II series of transmitters.
00809-0100-4303 November 2020 Configure Net Safety Millennium II Basic Transmitter When using the Net Safety ST3 sensor with the Net Safety Millennium II Basic Digital transmitter model (M2B-D), you can change the sensor's range by accessing a specific ® Modbus register.
Reference Manual November 2020 00809-0100-4303 Fault conditions The Net Safety ST3 sensor provides a number of fault conditions that the Net Safety Millennium II transmitter translates into an analog or fault relay output. These fault conditions are outlined in Table 3-1.
Replace sensor module Emerson pre-calibrates the sensors at the factory; however, you must perform field calibration as a part of commissioning. When the sensor end of life diagnostic indicates a fault condition, you can no longer calibrate, or the sensor is not working properly, you may need to replace the sensor module.
Troubleshooting Emerson did not design these sensors and transmitters to be repaired in the field. If problems should develop, first check for faulty wiring, confirm proper voltage to the sensor, and try to calibrate.
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ST341: 25 (O ST360: 1000 (CO) Ingress protection filter IPF-001 2-in. (50.8 mm) pole mounting kit UN-MK-32 Duct mounting kit UDM-001 (3.3 ft. [1 m] sampling pipe) UDM-002 (4.9 ft. [1.5 m] sampling pipe) UDM-003 (direct mount to duct) Emerson.com/FlameGasDetection...
Ensure ALL personnel are educated and trained in ESD control procedures. In general, exercise accepted and proven precautions normally observed when handling electrostatic sensitive devices. A warning label is placed on the packaging, identifying products using electrostatic sensitive semiconductor devices. Net Safety ST3...
Class 1, Zone 1, AEx d IIB+H T5 Gb Type 4X, IP64 IECEx Markings Ex db IIB+H T5 Gb -40 °C ≤ Tamb ≤ +75 °C Special Condition of Use: Flameproof joints are not intended to be repaired. Net Safety ST3...
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