NTC Thermistor Applications in Aircraft

The term “thermistor” is a combination of the words thermal and resistor. Negative Temperature Coefficient (NTC) thermistors are components within an electric circuit that lose resistance as they come in contact with increasing temperatures. They are widely used as temperature sensors in applications varying from microwaves to computers to the seat heater in your car. Not only do they measure temperature, thermistors also measure liquid levels, making their use in mechanical systems invaluable. What's more, NTC thermistors can operate between -55 to 200 degrees Celsius making them suitable for a variety of environments on an aircraft.

NTC thermistors are usually probes that are designed to be inserted into various components or small opening. Bead thermistors are the most common type of thermistor that are used on aircraft. The chip, or sensor components, is attached to the end of the probe. Platinum alloy is usually used to manufacture the bead. The sensor is encased in either a glass or epoxy casing depending on the substance or environment it is measuring. It reads the surrounding temperature and reports the data back to a control system where it can be read.

Thermistors are categorized further by the way they operate. Resistance temperature characteristic thermistors are often used for temperature control, measurement, and compensation. In this case, the probe cannot have any heat applied prior to the required reading. The standard base resistance is usually 25 degrees Celsius, which provides a convenient reference point. If the probe is already experiencing resistance from a latent heat source, the accuracy of the reading is compromised.

A variety of systems benefit from the application of NTC thermistors. Avionic equipment can be spared from an outage as the NTC thermistor absorbs the surge current across the equipment and protects it by changing its resistance. Cabin temperature control systems use the probes as regulation devices. As the temperature increases, the resistance of the thermistor decreases. When the current becomes too high, the system is switched on.

NTC thermistors are a necessary instrument within an aircraft as they help regulate the various systems. Without accurate temperature readings, the aircraft may experience issues that would otherwise be detected and corrected.

At ASAP NSN Parts, owned and operated by ASAP Semiconductor, we can help you find all the thermistors and temperature sensors for the aerospace, civil aviation, and defense industries. We’re always available and ready to help you find all the parts and equipment you need, 24/7-365. For a quick and competitive quote, email us sales@asap-nsnparts.us or call us at +91-714-705-4780.

1. john parker
2. Posted on July 11, 2019
aircraft components

Related Blogs