New Open-Thermistor Temperature Sensors Use Fused Glass to Eliminate Leakage

Open Thermistor TemperaturePlainville CT, April 2014

Fused glass is key to providing the leak-proof operation of these new open thermistor type temperature sensors from Gems Sensors & Control. The TM-950 Series temperature sensors utilize an open (exposed) thermistor design for faster response to temperature fluctuation than can be achieved with closed (encapsulated) designs. The TM-950 Series solves the sensed fluid leakage problem common with other open thermistor type sensors currently available. Originally designed for oil and refrigerants in HVAC and Chiller systems, TM-950 sensors can be used to monitor temperatures in any non-conductive fluid.

Product Engineer, Jim Dockendorff, explains what makes these new sensors unique: “TM-950 temperature sensors use an open (or exposed) design to place the ceramic thermistor in direct contact with sensed fluid. The open design is valued over encapsulated type sensors for their faster response time. The downside to most open thermistor sensors, however, is leakage through the housing where the thermistor leads pass through sensor housings, especially in pressured installations. In HVAC or Chiller systems this can cause significant maintenance and performance degradation issues. Gems TM-950 Series fuses glass inside the sensor housing, and uses inductive soldering around the thermistor leads to produce a hermetic seal. Leakage is eliminated while taking advantage of the quick responsiveness of an open, direct contact thermistor.”

TM-950 Series provide a standard referenced temperature sensing range of 32°F to 100°F (0°C to 38°C) and an over exposure capability range of -40°F to +250°F (-40C to +125°C). Any of a variety of thermistors may be utilized based on the temperature sensing profile required. Standard pressure rating is 450 psig (31 bar), with higher pressure capability available upon request. Wetted materials include zinc-plated steel, nickel-plated steel, Teflon®, ceramic, tin, and soda lime glass. Standard termination is IP65, 18AWG, PTFE insulated flying leads.

Click here for more complete specifications on the TM-950. For more product information, contact Gems Sensors & Controls, One Cowles Road, Plainville, Connecticut 06062. Phone: (800) 378-1600