12 Volt relay DC resistance

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Eric Lenius
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12 Volt relay DC resistance

#1 Post by Eric Lenius » Tue Jul 10, 2018 6:42 pm

Anyone know what the coil DC resistance is on typical 12V horn and headlight relays?

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Eric Lenius

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John Brooks
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Re: 12 Volt relay DC resistance

#2 Post by John Brooks » Tue Jul 10, 2018 8:04 pm

Eric

usually around 2-3 ohms for the coil.
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Eric Lenius
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Re: 12 Volt relay DC resistance

#3 Post by Eric Lenius » Wed Jul 11, 2018 1:19 pm

Do you mean 20 to 30 ohms?. At 2 ohms, the coil would draw 6 Amps at 12V. Dissipating 72Watts. Which, would result in a barbequed coil I think.

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Re: 12 Volt relay DC resistance

#4 Post by Hugo Karasawa » Wed Jul 11, 2018 8:10 pm

12v relays around 80 ohms.
6v relays around 40 ohms

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Re: 12 Volt relay DC resistance

#5 Post by John Brooks » Wed Jul 11, 2018 9:41 pm

Eric

I need to get one of thoes new digital meters. You are right the X10 switch makes the scale different. I just re read the relay, 27 ohms on the 6v and 77 on a 12v
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Eric Lenius
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Re: 12 Volt relay DC resistance

#6 Post by Eric Lenius » Thu Jul 12, 2018 12:26 am

Hi John,

Which relays are you checking? The resistance is different on the horn relays and the headlight relays I think....

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