How to select correct temperature sensor?

Temperature Measurement

How to select a Temperature sensor

** Performance Consideration**

1.Determine the range of temperature to be measured.

2.Identify the operating media that is being measured.

3.Determine the temperature accuracy (+ or - Degree ,+ or - % of reading)

4.Determine frequency response required.

5.Identify the temperature units you require

Fahrenheit Celsius Kelvin Rankine Reaumure

6.Determine over-temperature conditions? Will temperature ever exceed maximum of range? By how much?

Mechanical Consideration

1.Physical Size

Size constraints Probe length Location access

2.Process connection/pressure fitting

What is the maximum working pressure of the system?

  1. Characteristics of the media

Corrosive Viscosity Velocity On/Off cycling

Electrical Consideration


mV /V 0-5 Vdc,0-10 Vdc,other Bipolar voltage Isolated or Non-isolated voltage 4-20 ma Current


RS485 RS232


Analog and Digital

4.Electrical Termination

Connector or integral cable Customer specified Need for mating connectors and cable assemblies Connector / Cable orientation Wiring codes / Pin-outs

5.External Zero and Span

6.Specify the type of power supply

Environmental Condition

1.Operating Temperature Range

2.EMI/RFI conditions

3.IP or NEMA rating required

4.Hazardous environment

Intrinsic safe Explosion proof

5.Indoor or Outdoor use

Exposure to the element Dust dirt Temperature extreme Animal,critters,rodents etc.

6.Submersible or Subsea

Depth Case pressure

Special requirement

  1. Calibration requirement

2.Special approval / Certifications

3.Testing or Cleaning

4.Special Labeling requirement

5.Shock and Vibration resistance

  1. Serviceability

How accessible must the unit be? How often will it be serviced?