Lab+Life Scientist Jun/Jul 2017

Page 33

cold temperature monitoring

Paul Daniel and Jon Aldous

Chamber vs room monitoring


Which temperature sensors are best for your application?

Many chamber applications are cold temperature applications and usually temperature is the only parameter monitored. Cold air cannot hold much moisture so it is uncommon to use a humidity sensor in a cold temperature situation.


In our experience, when folks want to monitor cold temperatures, they simply select a vendor, then accept the sensor type that the vendor has decided here are four different sensor types

will work best in that particular application. So,

commonly used for cold temperature monitoring:

in many cases the decision of what sensor to use

• Mercury or alcohol thermometer.

is based on your choice of vendor. Monitoring

• Thermistor (thermal resistor).

does not require a high accuracy sensor for most

• Resistance temperature detectors (RTDs)

applications, especially for cold temperatures,

usually made from a pure metal, such as

so most types of sensors can be used with equal

platinum, copper or nickel, around a ceramic

efficacy. However, it can be valuable to understand

or glass core.

how each of the four types of sensors work in case

• Thermocouple, two wires of different metals.

there are variables in your environments that will

The junction between the two metals will show

cause one sensor to function better, last longer,

a voltage change from a change in temperature.

and measure more accurately. |

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