Electronic ballast grounding is good

[gregtwojeeps]

A few months ago I installed 5 hard wired surface mount Lowes (F32-T8 lamps x 2) lights on my garage ceiling, using the existing light circuit for their power. I had the lights on, as I was changing a broken 3-way switch cover plate. My left arm was grazing the overhead door metal track that is buried down in the concrete floor, as I was putting the metal screws in to the cover plate with my right hand....

Once when my finger touched the metal blade of my screwdriver, I felt a sharp "tingle" in my left arm that was touching the metal door track. A quick voltage check showed I had a 94 volt reading from my screwdriver blade while it was inserted in to the cover plate screw, to the door track.

I tracked the issue down to an open grounding conductor where the PO had installed a new fixture in the utility room (the garage ceiling lights were fed from it) and he had cut the equipment grounding conductor's off inside the outlet box ... for some reason .

So a trip in to the attic and with some new cable installed, I got the lights grounded and the voltage reading from the 3 -way switch frame to the door track reading "0". Be sure those electronic light ballasts are grounded properly guys !

 

[LXCam]

That isn't your only issue if I'm understanding you correctly. As long as your neutral integrity was 100% you shouldn't have gotten lit up by a missing ground. I would suggest you kill the circuit and do a ohm measurement between the ground and neutral conductors. It needs to be virtually 0. If it isn't start checking for a bad connection. You can also test your line to neutral and line to ground. The potential should be identical. If your voltage to ground is higher, once again start checking all your neutral connections.

 

[gregtwojeeps]

That isn't your only issue if I'm understanding you correctly. As long as your neutral integrity was 100% you shouldn't have gotten lit up by a missing ground. I would suggest you kill the circuit and do a ohm measurement between the ground and neutral conductors. It needs to be virtually 0. If it isn't start checking for a bad connection. You can also test your line to neutral and line to ground. The potential should be identical. If your voltage to ground is higher, once again start checking all your neutral connections.

Excellent points to consider but in my search just to get rid of the "shocking" garage door track I uncovered many electrical sins. I ran all new cabling for the utility room and garage which cured my shocking door track(your loose neutral diagnosis most likely was cured somewhere when I re-cabled) .

In my troubleshooting search I found even more problems with my 1959 model homes electrical system. (see my, " Should I be Skeered thread) One of the largest problems makes my search for proper neutral to equipment ground conductor readings... difficult and most likely a moot point..

I starting investigating to change out my 100 amp 1959 model electrical service. While doing so, I found the electrical service is not grounded anywhere. There is no EGC going down the brick wall from the meter base to driven rods and none from the breaker box going to driven electrode rods.

The 1959 breaker box needless to say, does not have a dedicated EGC terminal bar. All of the house's romex EGC's (what was left unmolested anyway) are connected to the neutral terminal bar in the breaker box...

The breaker box has a #6 bare copper conductor running from it in to the crawlspace where it is saddle clamped to a old 3/4 copper water pipe... that has been re-fed with PEX. As we know, the galvanized metal water lines from the street water meter back in the old days, were used a lot as the secondary ground electrode tandem to driven pipes or rods... our old house now has a 3/4 PEX for its buried main water line... So any expected "grounding" from water piping is moot...

On my path to getting a plan for changing the service I knew I needed to get a engineer from the POCO out to give me a new meter spot. When he showed up I told him the electrical service had NO grounding means other than the neutral being bonded at the transformer with its ground wire going down the pole and stopping at about 5 ft. below grade. The engineer did not seemed concerned about my home having no ground system and told me that was quite common to be, in these old houses. HUH ???

So I have problems to deal with. I am retired now and moved in to home with electrical/plumbing issues and now with my limited income, I am going to have to handle them like eating an elephant. Thanks for the reply

 

[LXCam]

Holy **** bud, I had no idea you've been doing your homework. Sounds like you'll get it all whipped in due time. Is normally say good luck but maybe due diligence pays off would be more appropriate.

 

[Mustang51js]

I was gonna say you have a loose neutral that you fixed while doing the work. The ground is mostly for if a hot wire falls off and touches the metal,it will cause the breaker to trip. You might have had a ground and neutral touching somewhere also. Good thing is it's all fixed

 

[wyliesdiesels]

OP- the wire going to grounding electrodes is called a GEC- grounding electrode conductor and is different than an EGC.

The abscence of the GEC and electrodes doesnt render your fault current grounding system(EGCs) useless. Grounding electrodes have NOTHING to do with clearing fault currents like what u experienced on your garage door track. This is because even though these 2 systems share a common name, they are different animals. Fault currents dont relie on nor flow on grounding electrodes. U can have a properly functioning EGC without a grounding electrode!

This is an OFTEN confused part of electeical systems even by electricians. Heres a good read to familiarize yourself with the subject:

http://www.electriciantalk.com/articles/the-confusion-of-the-term-grounding/

 

[gregtwojeeps]

OP- the wire going to grounding electrodes is called a GEC- grounding electrode conductor and is different than an EGC.

The abscence of the GEC and electrodes doesnt render your fault current grounding system(EGCs) useless. Grounding electrodes have NOTHING to do with clearing fault currents like what u experienced on your garage door track. This is because even though these 2 systems share a common name, they are different animals. Fault currents dont relie on nor flow on grounding electrodes. U can have a properly functioning EGC without a grounding electrode!

This is an OFTEN confused part of electeical systems even by electricians. Heres a good read to familiarize yourself with the subject:

http://www.electriciantalk.com/articles/the-confusion-of-the-term-grounding/

Wow, you mean for 30 years every time I installed a new service that whenever I drove two ground rods 8 ft. below grade and then run the bare copper conductor from them up to the meter base ... and bonded it under the MB's service neutral... that I did not really need to do it ? I am so pissed now. I want my materials and labor spent for installing a ground electrode system on those services way back then .... back now. Good to know my old house doesn't need a grounded service.

 

[wyliesdiesels]

Wow, you mean for 30 years every time I installed a new service that whenever I drove two ground rods 8 ft. below grade and then run the bare copper conductor from them up to the meter base ... and bonded it under the MB's service neutral... that I did not really need to do it ? I am so pissed now. I want my materials and labor spent for installing a ground electrode system on those services way back then .... back now. Good to know my old house doesn't need a grounded service.

Thats NOT what i said.

I never said u didnt need a grounding electrode system. It helps to pay attention.

I said the grounding electrode system isnt for clearing fault current. U had an issue with fault current. Then u mentioned u had no grounding electrodes. If u had grounding electrodes, u wouldve still had the fault current on the garage door track because the electrodes arent necessary for breakers to clear fault current.

EGCs and grounding electrodes are 2 different animals that serve different purposes...

Please read the link i posted!