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 preriodic calibration, troubleshooting or replacement. Gone
are the days of having to pull extension cables from cable trays, or disconnect the probe leads from screw terminals in a connection head, in order to calibrate or replace the sensor.
Now you simply disconnect the sensor from the extension cable saving cost and downtime. The M12 connector also provides two other important features, the keyed connector
eliminates the potential for mis-wiring during installation, and the elimination of screw terminals results in a more robust connection that will not loosen when exposed to heating and
The Series PR-31SL Spring Loaded RTD has been designed to provide our customers with a simple and effective way to adapt our M12 enabled RTD probes for use in thermowells.
To insure the best possible performance, the PR-31SL RTD has a spring loading feature that maintains contact between the probe and thermowell under static and vibration conditions.
This helps to maintain good heat transfer between the thermowell and probe, as well as dampening the effect of vibration on the sensor. With a demonstrated ability to withstand 10gs
of vibration between 10 and 500HZ (for 6" long and shorter probes per MIL-STD-202G, Method 204D, Test Condition A), this probe has shown its ability to withstand real-world conditions.
To select the right length probe for your application, simply measure the depth of the bore in the thermowell (the length from the top of the thermowell to the bottom
of the bore as shown as the "Thermowell Stem Length" in the sketch below).
The PR-31SL sensor assembly is designed to fit into a thermowell with a stem length equal to that specified in the model number. Simply
slide the sensor assembly into the thermowell until bottomed and then compress the spring while making the 1/2NPT connection. Thread sealant tape or
thread compound may be used on the 1/2NPT mounting thread to insure easy removal at a later time. The position of the self-gripping spring can also be
adjusted so that the sensor can be used in a shorter thermowell, simply twist the spring while sliding it along the probe stem until the needed position is reached.
The PR-31SL can also be used as a back-up sensor for a variety of applications. The spring loading feature can be adjusted to fit a variety
of thermowells. The spring loading fitting can be removed altogether and replaced with a compression type fitting if a fixed mounting is needed.
The probe (less spring and hex fitting) can also be used as a stand alone RTD probe. This flexibility in mounting options, as well as the simplified and robust connection provided by the M12 connector, makes the PR-31SL the perfect solution for a wide variety of applications.
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 connection. This allows for
simplified, trouble free installation with any existing application. This also allows the PR-31SL 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.
Standard Probe Diameter: 1/4"
Standard Probe Lengths: See Thermowell Stem Lengths in The Order Table Below.
Sensor: Pt100 (100 Ohms at 0°C, .00385 TCR (alpha)) Standard, Pt1000 and Other Options Available.
Accuracy: Class A Standard (per IEC 60751), Others Available Upon Request.
Temperature Range: -50 to 500°C Except for the Connector Which is 250°C Max.
Insulation Resistance: 100 Megohms Minimum at 100VDC at Room Ambient Temperature.
Vibration Resistance: 10gs from 10-500Hz per MIL-STD-202G, Method 204D, Test Condition A (6" long and shorter).
† All amounts shown in EUR, GBP, or USD Note: * Class A Accuracy = ±(0.15 + 0.002*t)°C where “t” = temperature in °C regardless of sign. For the alternate wiring arrangement, change “-1” to “-2” in the model number, no additional cost. For a probe length not listed up to 24", change the stem length in the model number to the required stem length (Example: 1250 = 12½") and use the price of the next longer sensor. Ordering Example: (1) PR-31SL-3-100-A-0250-M12-1 Spring Loaded Pt100 Class A RTD Probe with Molded M12 Connector, to Fit into a Thermowell with a 2.5 inch Stem Length, £68.00 plus (1) PR-31SL-3-100-A-0600-M12-1 Spring Loaded Pt100 Class A RTD Probe with Molded M12 Connector, to Fit into a Thermowell with a 6 inch Stem Length, £73.00, £68.00 + 73.00 = £141.00
Part Number Builder
Build Your Part Number Below
Probe Resistance select from: 100 for 100 Ohms at 0C 1000 for 1000 Ohms at 0C
Accuracy select from: A for Class A per IEC60751 B for Class B per IEC60751
Thermowell Stem Length select from: 0250 for 2.50 inches 0400 for 4 inches 0600 for 6 inches 0900 for 9 inches 1200 for 12 inches 1500 for 15 inches 1800 for 18 inches 2400 for 24 inches
Wiring Configuration select from: 1 for See Wiring Detail 2 for See Wiring Detail
Note: All combinations may not be valid, check spec sheet for valid part numbers.