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 »

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 »

Eric

usually around 2-3 ohms for the coil.
John Brooks

62 Roadster
66 912
84 Cab
getting pushed around in porsches since 1965

Eric Lenius
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Re: 12 Volt relay DC resistance

#3 Post by Eric Lenius »

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.

Hugo Karasawa
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Re: 12 Volt relay DC resistance

#4 Post by Hugo Karasawa »

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

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John Brooks
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Re: 12 Volt relay DC resistance

#5 Post by John Brooks »

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
John Brooks

62 Roadster
66 912
84 Cab
getting pushed around in porsches since 1965

Eric Lenius
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Re: 12 Volt relay DC resistance

#6 Post by Eric Lenius »

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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