Resistance For Electric Heaters Question
Resistance For Electric Heaters Question
(OP)
I have an electric heating strip. Let's say the heater's watts is 1000. The voltage is 208. From W=(V^2)*R, I determine that the resistance for the heater is 43.26 ohms. Is this correct?
If I change the voltage to a higher or lower number, does the resistance on the heater stay constant?
So if the voltage went to 220 volts, and the resistance stayed constant at 43.26 ohms, then my watts would go up. W=(V^2)*r => (220^2)*43.26= 1118.7 watts.
Is the above correct? Is the resistance of a resistor (in this case a heating strip) always constant?
I know that some resistors change resistance with temperature, but I should think that is not the case here.
Thanks in advance!
Bill
If I change the voltage to a higher or lower number, does the resistance on the heater stay constant?
So if the voltage went to 220 volts, and the resistance stayed constant at 43.26 ohms, then my watts would go up. W=(V^2)*r => (220^2)*43.26= 1118.7 watts.
Is the above correct? Is the resistance of a resistor (in this case a heating strip) always constant?
I know that some resistors change resistance with temperature, but I should think that is not the case here.
Thanks in advance!
Bill





RE: Resistance For Electric Heaters Question
P = (V^2) / R
RE: Resistance For Electric Heaters Question
ht
The effect is small, but nonzero.
TTFN
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RE: Resistance For Electric Heaters Question
Many heaters fail because dirt or other deposits build-up and cause the heater temperature to rise, although the watt output is the same.
RE: Resistance For Electric Heaters Question
RE: Resistance For Electric Heaters Question
Bill
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RE: Resistance For Electric Heaters Question
We use heater strips to simulate thermal load in electronic equipment testing. We've had heaters burn up so we usually dial down the voltage to a maximum of 75% allowable and use multiple heater strips to create the appropriate heat load.
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RE: Resistance For Electric Heaters Question
Bill