Someone has been callled to an Old Church to replace old decayed Fixtires through out, everything is going well until he et to the exterior lighting,
He finds a Missing Neutral Path for his Last Fixture checks again & No Meter Action from the Line, He thinks {i can't rewire in these old pipes) This Box is way out of the normal pedestrian traffic and says " what the heck" it'll look good completed and i could get paid in full today, SO: HE SHUNTS THE WHITE WIRE FROM THE FIXTURE TO THE BOX AND FINISHES INSTALLING THE PRETTY CHURCH LIGHTS.
How would you detect this condition ? what effect will it have on the system ? have you ever done this ?
The use of any term in front of "ground" only serves to confuse the issue. Grounds should be measured. Not assumed.
Multiple grounding of the neutral is very common and done by un enlightened persons. They think that it does not make much or any difference. Having a current carrying conductor grounded in any place other than the service can be dangerous. Will it work? Yes The amount of danger is dependant on the installation. I have seen it plenty. It is hard to find sometimes without sensitive equipment.
Call your local code authority and turn this hack in. File a law suit and get the money you paid back. No telling what other workmanship issues there are.
It is easily detected if the circuit originates from a panel that has separate buss bars for the neutral and Equipment Grounding Conductors. If you measure the current on the main bonding jumper and you find any significant current under normal operating conditions you have a ground fault somewhere.
If you measure the current with a clamp on current meter around both the grounded current carrying conductor (neutral) and the ungrounded current carrying conductor (hot) at the same time it should measure zero. Any measurable current is imbalance current which again indicates a ground fault.
You can use a simple continuity checker and having removed both the neutral and the hot from their respective terminations in the panel there should be no continuity between either current carrying conductor and ground. Continuity indicates a ground fault.
Under normal circumstaces it would go undetected. You might discover the problem if a repair was needed.
However, if you were actively looking for the problem, it is relatively easy to determine if it exists. Shut off all the branch circuit breakers. Disconnect all neutrals at the panel. Turn on all the breakers, except for those serving multiwire branch circuits, and see what circuits are live. Any live circuit means that the neutral is erroneously grounded. If such a ground is suspected on a multiwire branch, you will need to remove one of the hot wires and the neutral at the panel, then see if half the branch is live. You will need to do that for both halves of the multiwire.
Once you know that a branch has an erroneously grounded neutral, you need to disconnect at junction boxes to determine where the ground exists.
None in the situation you described. But if the metal pipe somehow becomes electrically open, then there is a safety hazard.
the practice is not employed here and is seriously discouraged
was wondering what type of meter tests on a Panel and system I could perform to detect such a violation.
the Electrician was me and I didn't terminate the job until i can dig up or re wire for a safe & hazard free job..
I was a little tempted but a water puddles right underneath this particular outlet and just couldn't, though I Joked about it giving any pheligrees walking by it a tingly neary Religious experience };-)
I'd never leave a dirty ground conditon on an active circuit., though, the screw on the box is a good Test Grnd for lighting that is as far as i'd go with this temporary use.
Okay the removing the white wires off ground buss and testing for voltage at the neutral Panel & Buss would detect this GF condition: To Much Trouble & it would leave all curcuits ungrounded. Not To Good an Approach.
maybe a quick check between the Line Ground or Neutral Buss and the Panel Chassis.... I might recreate the condition in my apt. test & record results..
No GFCI breakers back in those days, hell they didn't even have computers when I refurbished some shot circuits, that one Here was left undone, I taped breaker taped off., capped & taped both leads, pushed them back in the box and put a plate over it for the future...
I just think it's a good servce protocol when wiring new equipment or circuits for clients.I would like to perform the test on all of my calls. Here we are };-)
There are no white wires on the ground bus in a properly wired panel - only green or bare. If you left the wires off the ground bus and tested for voltage with respect to the neutral bus you would see whatever the line voltage is (120 vac, nominal) on your meter. The neutral bus is connected to the ground bus by the main bonding jumper (which is not a white wire), so it remains at ground potential. It would not show that a neutral was "re-grounded".
The problem you described is that the neutral wire was open to a light fixture. Let me draw it: neutral------- break ----------fixture. The "fix" was "regrounding" at a point after the break, at the fixture: neutral------- break
-------"reground"--fixture If you disconnect the broken neutral wire at the panel, it will not show the "reground" - it is not connected to it.
You have to remove the neutral wire, at the panel, and test with a load connected at the ends of the branch to know if a neutral has been "regrounded" in the problem you described. You could test from the panel with an ampprobe to look for current on the hot wire - but that is too much work, walking back and forth from the panel to each end of the branch, connecting a load, walking back to the panel to look at the ampprobe etc. Just disconnect the neutrals at the panel restore power (leaving multiwire circuits off) and walk to each end of the branch circuits and test. Since you don't know where the ends are, you have to test *every* outlet. You have to perfrom that test on each side of any multiwire branches, turning on one half, performing the test, turning it off, turning on the other side and testing again. Any outlets that show as live have a "reground". It is the only way to be 100% positive that no "regrounds" exist. Unless there was a compelling reason to do all that work, no sane electrician will do it in the normal course of events.
In the real world, the problem would be discovered, if it was discovered at all, when something went wrong or in the process of renovation or changing the fixture for some reason other than repair.
no no no, the neutral from panel for the light fixture is damaged (shunted to the Hot wire or broken) No Neutral is presnt at the fixture box outside n the wall about 8ft above the path to the rectory.
connectng the fixture i discovered the problem when the lamp didn't come on, os I figured a disconnected neutral at the panel cause i had "juice" but no ground but from the box. turned out: That Circuit was connected to it's circuit breaker so was the neutral {perplexing} I figured it got shunted and broke underground somewhere and left it alone for some other time & budget.
maybe it is shunted somewhere else along the run but it's a comlpicated old structure with about a dozen panels I hit it for a half hour and got tired of poking in & around boxes for the fault & left.
I may look into it for them again and re route a new circuit to the box.
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