At the end of this module, you will be able to:
- Identify and describe the different types of temperature sensors
- Differentiate between contact and non-contact temperature sensors
- Differentiate between the different classifications of thermistors
- Identify and describe the different types of light sensors
- Explain how the different types of light sensors work
The following key questions are answered in this module:
What's the purpose of a temperature sensor?Temperature sensors help ensure that a process or application is operating within a safe temperature range. They also aid in measuring the temperature of equipment operating under hazardous conditions or in an area inaccessible by normal means.
What is a thermistor?A thermistor is a small, easy-to-use thermal sensor designed for measuring temperatures in hard-to-access locations, like the inside of a motor's coil.
What is a Resistive Temperature Detector (RTD)?An RTD is a temperature-sensitive resistor made of a pure metal such as platinum, nickel, or copper.
What is a thermocouple?Thermocouples are temperature sensors that measure voltage changes between two dissimilar metals.
What are some applications of light sensors?Light sensors are used to detect light. They are used in consumer products, security alarms, retail establishments, and in scientific applications.
Below is a transcript of the video sample provided for this module:
PTC thermistors are typically used in switches. This is because when a specified critical temperature is reached within a device, their resistance spikes and stops current flow. NTC thermistors are typically used in alarming devices, because their ambient temperature-resistance is high. For example, within a fire alarm, the NTC thermistor keeps the amount of current going to the alarm low when there is no fire. However, if a fire occurs, the ambient temperature increases, allowing more current to flow into the circuit, eventually triggering the alarm.
Use the additional resources and links below to learn more about this topic: