Voltage Problem - Lighting Circuit

What I'm thinking is, since I can't see the wire running down the wall to the switches, and since this circuit has only lights on it,
put a AFCI in the panel to cover that unknown. Actually I just don't wan't to tear apart the wall - and remove all the shelves and such.
These two (4) bulb fixtures, (4) Fluorescent twin-tubes, and the LED outside.
 
Check all your neutrals, if one or more are loose, the ground ends up becoming the neutral and you'll see a low voltage. This happened to me about 2 months ago installing a new receptacle
 
aliva said:
Check all your neutrals, if one or more are loose, the ground ends up becoming the neutral...
Click to expand...
This can only happen if you have a neutral to ground fault somewhere. If any current flows with the neutral interrupted something is very wrong. A loose neutral in the box can cause low line to neutral voltage at the load, though.
 
Let there be light!
P1080113r.jpg
And now I need an education or lesson in electricity.
Before I screwed everything back together I tested the fixture without the ground attached.
Gloves on, power on, no bulbs, I connected the Fluke to the ground inside the box and contacted the outside of the bulb housing
and it was reading 4.8VAC and the detector was squealing. Nothing on the Neutral to Ground.
Connected the ground and all's good. I guess I just don't understand the basics of AC power.
I checked out both fixtures on the bench before I wired them back up, checking to see if any of the sockets or the switches were
shorted to the metal case. They were all good. I am so confused. Too many wires in the socket portion of the fixture?

Thanks.
 
The neutral and ground are connected at the main panel, so seeing continuity is OK. However, you should see zero voltage potential. Have you checked for potential between the neutral and ground with the fixture removed from the circuit (obviously cap the hot and move carefully)? If that is zero, stop and throw away the fixture. If not zero, then check at the panel between the neutral and ground. If that shows potential, something is really wrong.
 
middle.road said:
Let there be light!
View attachment 114057
And now I need an education or lesson in electricity.
Before I screwed everything back together I tested the fixture without the ground attached.
Gloves on, power on, no bulbs, I connected the Fluke to the ground inside the box and contacted the outside of the bulb housing
and it was reading 4.8VAC and the detector was squealing. Nothing on the Neutral to Ground.
Connected the ground and all's good. I guess I just don't understand the basics of AC power.
I checked out both fixtures on the bench before I wired them back up, checking to see if any of the sockets or the switches were
shorted to the metal case. They were all good. I am so confused. Too many wires in the socket portion of the fixture?

Thanks.
Click to expand...
There's nothing wrong. There is a tiny amount of capacitance between the hot wire inside the fixture and housing. The Fluke has an impedence of 10 Megohms so the fraction of a microamp of current that flows through this capacitance shows up on the Fluke as a few volts.
 
John Hasler said:
There's nothing wrong. There is a tiny amount of capacitance between the hot wire inside the fixture and housing. The Fluke has an impedence of 10 Megohms so the fraction of a microamp of current that flows through this capacitance shows up on the Fluke as a few volts.
Click to expand...

Love my Fluke digital but sometimes the old analog Simpson 260 just works better :)
 
CluelessNewB said:
Love my Fluke digital but sometimes the old analog Simpson 260 just works better :)
Click to expand...
I've got a couple of 260's sitting in a drawer, I would say it is time to dust one off and change the batteries. :grin:

Time to get off my arse and install the grounding rods. I've been pondering a run to the old well casing, but there's the distance and two sidewalks to contend with.
I've got the house main panel and the sub panel in the garage to do.
 
Crap, I read that as 48V. Yes, 4.8V will be from induction or capacitance. Which one is academic. I am sorry for not reading more carefully.

If it was 48V, then my comment is still probably an OK approach.

Mea culpa,

Tom
 
tomw said:
Crap, I read that as 48V. Yes, 4.8V will be from induction or capacitance. Which one is academic. I am sorry for not reading more carefully.

If it was 48V, then my comment is still probably an OK approach.

Mea culpa,

Tom
Click to expand...
Fault? whose fault? Those decimal points get trickier with age - I hear. All good. I was hoping it was a force field of some sort.
Didn't feel like going out and finding new fixtures. Would like to go LED as soon as the budget allows.

In other news - I revived one of my simpsons... Forgot how many batteries those puppies take.
 
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