If you have a temperature application but are unsure about which sensor you need to use – take a look at the considerations below.
Temperature range should be the first consideration when selecting a temperature sensor for an application. Different temperature sensors will be more suited to different ranges.
NTC thermistors are well suited to applications from -50° up to +250°C and so are well suited to a range of applications.
Thermocouples are less accurate at lower temperatures but are able to measure temperatures up to 2000°C.
The required accuracy is another important consideration. Thermocouples, although they are low cost, are often less accurate over time than a thermistor temperature probe.
NTC thermistors and thermistor probes are the most accurate between -50C and +150°C and if they are glass encapsulated can also be extremely accurate at 250°C.
Is the operation long term? This will affect the type of temperature sensor which is used. Temperature sensors can become less effective over time depending on their construction, materials they are constructed from and the packaging.
Over the course of a year, a thermistor can change by 0.02°C to 0.2°C depending on whether or not it is hermetically sealed. A Thermocouple can change by 1°C - 2°C over the course of a year.
The packaging style will differ depending on the application in hand. A threaded stud may be used for some general purpose applications. Closed tubes are well suited to applications involving liquid measurement. For surface sensing, ring terminals and other thin round metal stampings can be used.
NTC thermistors possess high resistance during the initial switch on making them immune to electrical noise and lead resistance. Thermocouples are also immune to lead resistance although can be affected by electrical noise because of the small output signal.
For more information on the temperature sensors we can offer take a look at our Temperature section on our website. You may also find our NTC thermistor page useful. Many of our temperature sensors are bespoke so please contact us if you have a requirement: +44(0)1327 351004 or email@example.com
For more information please contact: Variohm EuroSensors Ltd Email: firstname.lastname@example.org Tel:+44 (0) 1327 351004 Fax: +44 (0) 1327 353564
Article date: 17 / Jan / 2019
Selecting Temperature Sensor; Things to Consider
Published by: Variohm EuroSensor
From 20th January 2017 Variohm Eurosensor Ltd is part of the discoverIE plc Group of companies
Variohm EuroSensor,Williams' Barn, Tiffield Road,Towcester, Northants NN12 6HP.
Tel: +44 (0) 1327 351004.
Fax: +44 (0) 1327 353564.