Help with resistors in parallel

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Steve
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Help with resistors in parallel

Post by Steve » Sat May 01, 2021 9:16 pm

Hey guys,

If I replace a blown resistor with 2x resistors in parallel, would this allow them to be more tolerant to the heat / wattage passing through, ie share the load?

resistor-res76.gif
resistor-res76.gif (2.54 KiB) Viewed 320 times

So for instance, if the original resistor that blew was 500ohm, I would put 2x 1kohm resistors in parallel right? But yeah, would this be effective and make it more reliable? (of course I know you can get higher wattage resistors, but if you don't have any etc would this work)

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bfollowell
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Re: Help with resistors in parallel

Post by bfollowell » Sat May 01, 2021 9:38 pm

Yes, in your example, two 1Kohm resistors in parallel would be equivalent to a 500ohm resistor. I have no idea how tolerant the combination would be in relation to heat or stress compared to a single resistor.

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Re: Help with resistors in parallel

Post by Maximilian » Sun May 02, 2021 1:54 am

Yes, the total amout of power will be divided between the two resistors.

So if the original resistor is 1/4th of a Watt and the two replacements are also 1/4th of a Watt, the replacements will be a lot cooler.

Make sure that the resistors have enough room between them so that they do not heat up each other.

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Steve
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Re: Help with resistors in parallel

Post by Steve » Sun May 02, 2021 7:13 pm

Thanks guys much appreciated :)
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