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TT 30 P question. No neutral - 60 volts each leg

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Steve Crump:

--- Quote from: Kemper Watson on June 25, 2023, 11:39:01 AM ---   Yesterday we found a TT 30p on the side of a house where we were providing audio . Homeowner says its what they've used before. They have it adapted down to Edison so I plug in a tester. No neutral. Further inspection show 60 volts from each blade to ground  Measuring across the two blades gave 120 volts..How did this happen? I can't recall seeing 60 volts before..? We abandoned this and found grounded/correct circuits and pulled from them..Thanks for your time!!

--- End quote ---

Not seeing the install or understanding how it is connected up the line, I would say this house has a grounding issue. Usually, you see this when a transformer is part of the circuit and has not been properly bonded. 

John Roberts {JR}:
The obvious question is what is your ground 0V reference for making those measurements? I've seen roughly 1/2 voltage measured wrt a floating ground.

Can the edison outlet support a drop light with one lamp?

What did you use for an outlet tester? The highest likelihood is that you see 120VAC between line and neutral.

Slowly back away... maybe tell the homeowner to wire in a GFCI edison outlet if he must.

JR 

Kemper Watson:

--- Quote from: John Roberts {JR} on June 25, 2023, 02:55:24 PM ---The obvious question is what is your ground 0V reference for making those measurements? I've seen roughly 1/2 voltage measured wrt a floating ground.

Can the edison outlet support a drop light with one lamp?

What did you use for an outlet tester? The highest likelihood is that you see 120VAC between line and neutral.

Slowly back away... maybe tell the homeowner to wire in a GFCI edison outlet if he must.

JR

--- End quote ---


I have the male Edison plugs with the red/green lights. While I know they're not perfect but when I see red I go looking for something wrong. Went and got the meter and found 60v to ground on each leg. I'm not an electrician so that's all I know to do. I knew once I saw the 60 v I wasn't using it

John Roberts {JR}:

--- Quote from: Kemper Watson on June 25, 2023, 03:29:33 PM ---
I have the male Edison plugs with the red/green lights. While I know they're not perfect but when I see red I go looking for something wrong. Went and got the meter and found 60v to ground on each leg. I'm not an electrician so that's all I know to do. I knew once I saw the 60 v I wasn't using it

--- End quote ---
This is probably TMI but those three lamp testers are not very accurate. In fact they can report a good outlet that isn't.

 If they report a bad outlet, it usually is bad.

 http://johnhroberts.com/OD1.htm


JR

frank kayser:

--- Quote from: John Roberts {JR} on June 25, 2023, 04:03:31 PM ---This is probably TMI but those three lamp testers are not very accurate. In fact they can report a good outlet that isn't.

 If they report a bad outlet, it usually is bad.

 http://johnhroberts.com/OD1.htm


JR

--- End quote ---
Sure do wish someone could make this tester a reality

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