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Vibration Resistant Platinum RTD (PT100) Sensor with M12 Connector and Mounting Thread

Item# PR-21-B-3-100-A-1/4-42-M12-1

Vibration Resistant Platinum RTD (PT100) Sensor with M12 Connector and Mounting Thread PR-21-B-3-100-A-1/4-42-M12-1 PR-21-B-3-100-A-1/4-42-M12-1
  • Integral 4-Pin M12 A-Coded Male Connector for Easy Installation. An M12 Extension Cable is Required for Installation.
  • Available With a Variety 316L SST Threaded and Non-Threaded Housings
  • Pt100 or Pt1000 Class A, 4-Wire Platinum RTD Elements per IEC60751 Standard
  • Available with 1/4", 1/8", 6mm and 3mm Probe Diameters and a Wide Variety of Standard Lengths
  • Two Wiring Arraingements Available to Match Any 2, 3 or 4-Wire Requirement.
  • Temperature Range -50 to 250°C (-58 to 482°F) Sensing End, 85°C Max at Connector
  • Fast Response Time (3.5 Seconds or Less 63% Response in Water)
  • Vibration Tested to 10g's (10 to 500Hz per MIL-STD-202G, Method 204D, Test Condition A), 6" Long or Shorter.
Resistance or Output Type
Temperature Accuracy
Number of Wires
Probe Diameter
Probe Length
Mounting Style
Electrical Connection Type
Maximum Temperature Measurement
Minimum Temperature Measurement
Additional Features
See All Options
Quantity Price each
1-9 $122.06
10-24 $115.96
25-99 $109.85
100-499 $103.75
500-999 $97.65
1000+ $91.55

In stock

Lead Time ( If not in Stock): 3 weeks

Product Specs

  • Measurement Type Temperature
  • Minimum Temperature Measurement -50°C (-58°F)
  • Probe Material Stainless Steel
  • Response Time 3 Seconds Max (63.2% Response) When Immersed in Water Flowing at 3 feet/sec

See our New Higher Temperature, Bendable RTD Sensors at PR-26

Note: These Sensors Require an M12 Extension Cable to Connect the Sensor To Your Instrumentation. A Partial List Of Our M12 Extension Cables is Included in the Ordering Table Below.

Our RTD sensors with M12 connections provide for easy and efficient installation or removal of these sensors for periodic calibration, troubleshooting or replacement. Gone are the days of having to pull extension cables from cable trays in order to calibrate or replace the sensor, now you simply disconnect the sensor from the extension cable saving cost and downtime. The Omega PR-21 RTD is a flexible and robust temperature sensor constructed with 316L Stainless Steel housings and sheaths for strength and corrosion resistance. These sensors include a 4-pin, M12 A-Coded plug connector for easy assembly to patch cables or extension cables, as well as a variety of "NPT" pipe thread and metric mounting thread options for easy installation into a wide variety of threaded ports. A non-threaded housing option is also available for other types of installations.

For use in thermowells, the PR-21SL Spring-Loaded version of this sensor is the preferred solution. The PR-21SL design includes a non-threaded PR-21A style probe with a self-gripping spring and 1/2NPT threaded fitting to insure that the probe will contact the bottom of the thermowell bore without damaging the sensor. This insures that the sensor length will always be a perfect fit for your thermowell. See the PR-21SL page for additional information.

The mounting thread options on the PR-21 Series sensors allow them to be used in a wide variety of applications, including:
  • Stand alone immersion sensors.
  • Installed directly into your product or process using an existing NPT or metric threaded port.
  • When combined with our M12-Handle, non-threaded "A" style PR-21 probes can be used in hand-held sensing applications.
  • Other applications using a variety of available compression fittings or other accessories.

  • These RTD sensors can be used in any 2, 3 or 4-wire application by selecting one of the two available wiring arrangements (see the wiring diagrams below) and using only those wires needed for your measurement connection. This allows for simplified, trouble free installation with any existing application. This also allows the PR-21 series sensor to be used for a wide variety of replacement applications since it can be connected as-is with just about any measurement or control equipment available when combined with a 4-pin female M12 connector extension or patch cable.


    When ordering your PR-21 sensor, don't forget your extension cable. Omega offers a wide selection of extension cables including over molded PVC, Polyurethane and Silicone cables, as well as customized cables in a variety of materials with optional stainless steel braid or hose for improved mechanical protection, and a wide selection of instrument connections.

    Connect your PR-21 RTD sensor to one or more of Omega's wide variety of in-stock controllers, data loggers, transmitters, hand held thermometers, PLCs, or other measurement & control products to complete your measurement or control system. Omega offers a selection of programmable and fixed range transmitters that can be connected directly to the M12 connection of your PR-21 sensor. There are also wireless transmitter options available.

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