Probes Unlimited Custom Sensor Solutions
Probes Unlimited, Inc. provides custom temperature measurement and control devices for OEM applications, offering a wide range of RTDs, thermocouples, thermistors, thermal switches, cable harnesses, stainless steel tubing and more.
We primarily sell to equipment manufacturers of the following industries: Commercial Food Service, Packaging, Laboratory Apparatus & Pharmaceutical, Energy Management, Plastics, HVAC/R, OEM's, Medical, Aircraft & Aerospace, Waste Treatment, and several others.
Resistance Temperature Detectors (RTDs)
Resistance temperature detectors or resistive thermal devices (RTDs) are temperature sensors that consist of a wire coil wrapped around a ceramic or glass center. The sensor exploits the predictable change in electrical resistance of some materials with changing temperature. The most widely used sensor is the 100 ohm or 1000 ohm RTD platinum resistance thermometer.
RTDs are the most accurate sensors for scientific and many other applications and also offer the best long-term stability. A representative value for the accuracy of a platinum resistance is +0.5 percent of the measured temperature. After one year there may be a shift of +0.05°C through aging. Platinum resistance thermometers can cover temperature ranges from -200 to 800°C.
Thermoelectric devices for measuring temperature consisting of two wires of different metals connected at two points - both ends and one junction. One junction is set at the temperature to be measured and the other is held at a fixed lower temperature. The voltage generated in the circuit between the two junctions is proportional to the temperature difference.
Thermistors are often called negative temperature coefficient (NTC) sensors. A thermistor is a semiconductor device made of materials whose resistance varies as a function of temperature. They can be used to compensate for temperature variation in other components of a circuit. Because of their low cost and the simple circuitry required, they are preferred in many applications to more expensive thermocouples and RTDs. In addition, they can be produced in very small designs with a fast response and low thermal mass.
For more information on our Probes Unlimited offerings, please contact Heilind.