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#### DJB123090

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Hi Guys I have a questions in regards to getting continuity on a circuit I have off at the breaker.

So I will explain what had me perform the test in the first place, I am currently remodeling my kitchen and the girlfriend was requesting a switch to control the light over the sink since the old one used a pull string. So I got everything wired up and I wanted to make sure that I didn't have any shorts in my wiring. I performed a check at the terminals where the light will connect and I had continuity. I thought it was my wiring but I traced the wire to the wall and to a box where it got fed power and connected the light and an outlet below, I cut the wires to perform another check and it was not from my wiring or the outlet but when I measured the wires coming in to feed the circuits and again had continuity. Attached is a drawing of the circuit I tested. I wanted to add though when the circuit has power everything works as it should. I think this circuit has been this way since I owned the house but I didn't notice till the kitchen renovation. I'm at a loss of why would the circuit work if there is a "short"??

#### de-nagorg

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A one poster can't add pictures, try that again.

My first impression is that this is a 3 way circuit, and you have tapped one leg of it.

ED

#### chetwisner

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176 Posts
A short circuit would show 0 ohms on a digital, and full scale on an analog. Finding resistance just shows there's a load somewhere. It's not to be worried about.

#### seharper

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Yeah, loads count as limited-resistance shorts. Say you have two 60W bulbs (because it's 1977): That's 120W.

Watt's Law (to get amperage)
P = EI
120W = 120V x I
1.0 = I

Ohm's Law (to get resistance from amperage)
E=IR
120V = 1.0 * R
R = 120 ohms

You generally should avoid tapping power at a switch. Switches often don't have always-hot and neutral, and often have weird stuff (3-ways).

#### DJB123090

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Attached is the diagram of what I tested, please note that there are more receptacles between the breaker and where i'm testing with the meter.

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#### brric

· Master Electrician
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Is there a light bulb in the fixture with the switch in the “on” position?

#### DJB123090

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Is there a light bulb in the fixture with the switch in the “on” position?
no there was not but this circuit does tie into my porch light.

#### beenthere

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42,671 Posts
Your drawing shows the switch in the common. Thats not allowed.

seharper
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