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Temperature sensor

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Strablan

New Member
Hi all

I am wanting to build a controller for a heating system, the pic I have
attached shows the temperature sensor part. The problem I have is that the only suitable thermistor that I can source is rated 100k not 33k as listed in the diagram. My question is what changes would I have to make to the other resistors to be able to use the 100k thermistor?

A1/2 are LM311 comparators
R18 & R20 are potentiometers

Many thanks for any help
 

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k7elp60

Active Member
Change R16 from 51K to 150k. When the 33K thermistor is 33K at some temperature the voltage at the junction of the thermistor and R16 will be
2 Volts. Putting a 100k thermistor in place of the 33K and a 150K resistor in place of R16 will accomplish the same.
 
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