I have a wire wound resistor that is changing too much when being heated and cooled. I know changing the chemical composition of the wire is the biggest factor in changing the temperature coefficient of resistance (TCR) of the wire, but I already have wires with a larger diameter of the same material. Although the resistivity of these wires would be lower, would the TCR improve? There would also be more wire on the resistor. I cannot find anything online that relates to this.


1 Answer 1


Changing the diameter of a wire does not effect the TCR of a wire. However the TCR is not necessarily linear. The TCR at a high temperature could be higher or lower than it is at room temperature. Of course a change in diameter will change the resistivity. Using a larger wire to make a resistor of the same value will mean that the temperature will not increase as much for a given power dissipation because there is more surface area available to transfer heat our of the wire.

  • \$\begingroup\$ In the testing, the resistor is in a hot environment, not by powering the resistor. So the only way to improve upon this is to change materials? \$\endgroup\$
    – Jon
    Nov 20, 2019 at 15:37
  • 2
    \$\begingroup\$ Yes, if the environment temperature changes a lot, you would need to find a material with a lower TCR. \$\endgroup\$
    – user80875
    Nov 20, 2019 at 16:04

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.