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49528867
Premium
join:2010-04-16
Fort Lauderdale, FL
kudos:3

1 recommendation

reply to Jack_in_VA

Re: The most screwed up electrical work I have ever seen.

said by Jack_in_VA:

The pump circuit probably and most likely has a ground wire inside the conduit bonding everything to ground. Therefore the conduit even though it has teflon tape would be grounded on either end. In such case it doesn't matter about the conduit in that case but it sure makes a difference with the explosion hazard.

Incorrect and here’s why, by applying plumbers dope or tape to sections of conduit, those sections of “metallic conduit” become isolated from the grounding path and if an energized conductor within that conduit for whatever reason was to make contact within that isolated section of the conduit it would energize it and lacking a solid path to ground such a fault would fail to pull enough amperage to activate the upstream protective device and create a hazardous electrical condition.

Wayne
--
Madness takes its toll, please have exact change ready…


Jack_in_VA
Premium
join:2007-11-26
North, VA
kudos:1
Reviews:
·Millenicom

1 edit

What? Creative at best Wayne. We had such a problem with adverse environmental conditions, rust, corrosion etc that the physical electrical integrity of the threaded connections could not be guaranteed. Thus all our circuits and motor feeders had to have a ground wire pulled in. We even had PVC inserted in some places in a regular rigid galvanized conduit run and Stainless Steel conduit. Neither a good conductor. Agree?

BTW you said that was the "Most screwed up electrical work you have ever seen" That is good compared to some I've seen.



49528867
Premium
join:2010-04-16
Fort Lauderdale, FL
kudos:3

2 edits

said by Jack_in_VA:

What? Creative at best Wayne.

Plumbers dope aside...

Jack what I posted is based on the NEC not creativity...

Ever heard of concentric knockouts?

Based on my already posted comments, any idea of the code requirements if one was to run a metallic conduit from a meter can to a breaker panel if either of those metallic cans have concentric knockouts???

And if you do, then why do you think the code requires a grounding bushing on that metallic conduit when it is already being connected to two well grounded metallic cabinets???

Himmm.

We had such a problem with adverse environmental conditions, rust, corrosion etc that the physical electrical integrity of the threaded connections could not be guaranteed. Thus all our circuits and motor feeders had to have a ground wire pulled in. We even had PVC inserted in some places in a regular rigid galvanized conduit run and Stainless Steel conduit. Neither a good conductor. Agree

What I would agree with is where you worked should have been shut down and those in charge of maintenance prosecuted for the numerous violations and hazardous conditions you just mentioned.

There is NO excuse for allowing such crap to exist.

Time to put the shovel away guy as the hole you are in is deep enough…

Wayne

--
Madness takes its toll, please have exact change ready…


Jack_in_VA
Premium
join:2007-11-26
North, VA
kudos:1
Reviews:
·Millenicom

1 edit

Can't resist an attack when someone questions you can you?
Your little sanitized world is evidently no where close to the real world with real world conditions and requirements. Not a simple meter pan hookup. What's with the concentric knockouts? It was an industrial facility and fully complied with and met all applicable requirements.

You would not last a week in that plant.



49528867
Premium
join:2010-04-16
Fort Lauderdale, FL
kudos:3

said by Jack_in_VA:

Not a simple meter pan hookup. It was an industrial facility and fully complied with and met all applicable requirements.

Based on what you already posted about where you worked that seems not possible...

To me what you described sounds like a plant that belongs in a third world county where the cost of an incident is weighed low against corporate profit.

Kinda like the Dow Chemical incident in Bhopal…

Wayne
--
Madness takes its toll, please have exact change ready…


Jack_in_VA
Premium
join:2007-11-26
North, VA
kudos:1

nm


harald

join:2010-10-22
Columbus, OH
kudos:2
reply to 49528867

I'm surprised that no one has commented on the "field redesign". The control box has been turned 90 degrees from its original location. Who knows how they handled all the gas and electrical connections.



49528867
Premium
join:2010-04-16
Fort Lauderdale, FL
kudos:3

1 edit
reply to Jack_in_VA

said by Jack_in_VA:

What? Creative at best Wayne.

250.100 Bonding in Hazardous (Classified) Locations.
Regardless of the voltage of the electrical system, the electrical continuity of non–current-carrying metal parts of equipment, raceways, and other enclosures in any hazardous (classified) location as defined in Article 500 shall be ensured by any of the methods specified in 250.92(B)(2) through (B)(4) that are approved for the wiring method used. One or more of these bonding methods shall be used whether or not supplementary equipment grounding conductors are installed.

Note the use of the term shall because in the code shall means something important.

250.92 Services.

(B) Method of Bonding at the Service. Electrical continuity at service equipment, service raceways, and service conductor enclosures shall be ensured by one of the following methods:
(1) Bonding equipment to the grounded service conductor in a manner provided in 250.8
(2) Connections utilizing threaded couplings or threaded bosses on enclosures where made up wrenchtight
(3) Threadless couplings and connectors where made up tight for metal raceways and metal-clad cables
(4) Other listed devices, such as bonding-type locknuts, bushings, or bushings with bonding jumpers

Wayne
--
Madness takes its toll, please have exact change ready…


49528867
Premium
join:2010-04-16
Fort Lauderdale, FL
kudos:3
reply to Jack_in_VA

said by Jack_in_VA:

What's with the concentric knockouts?

It was an example of how important a good path to ground is and the fact that even though a concentric knockout provides a metallic connection it is insufficient to be trusted to handle fault currents.

Now if a concentric knockout is insufficient, doped up threads are truly insufficient.

250.92 Services.

Bonding jumpers meeting the other requirements of this article shall be used around concentric or eccentric knockouts that are punched or otherwise formed so as to impair the electrical connection to ground. Standard locknuts or bushings shall not be the sole means for the bonding required by this section.

Wayne
--
Madness takes its toll, please have exact change ready…


Dude111
An Awesome Dude
Premium
join:2003-08-04
USA
kudos:12
reply to 49528867

 

Yup its sickening..... People do the shittiest jobs they can BUT STILL WANT THE SAME PRICE FOR GOOD WORK!



sayitaintso

@sbc.com
reply to 49528867

Re: The most screwed up electrical work I have ever seen.

So, did you turn them in, or did you lower your head and walk away silently?



cdru
Go Colts
Premium,MVM
join:2003-05-14
Fort Wayne, IN
kudos:7

said by sayitaintso :

So, did you turn them in, or did you lower your head and walk away silently?

At minimum, I'd run away.


FiReSTaRT
Premium
join:2010-02-26
Canada

I've seen an RTU that was wired so creatively that it had marettes exposed to the elements, with the open portion pointing up. Another win for the lowest bidder



Nick_L
Premium
join:2003-01-22
Pittsburgh, PA
reply to 49528867

Since we're doing Q&A, if you don't mind, would you explain eccentric knockout? Concentric I understand.

Thx



49528867
Premium
join:2010-04-16
Fort Lauderdale, FL
kudos:3

said by Nick_L:

Since we're doing Q&A, if you don't mind, would you explain eccentric knockout? Concentric I understand.

Thx

Whereas a concentric knockout has a blank plug surrounded by larger and larger rings an eccentric knockout has the blank plug against the edge of cabinet surrounded by larger and larger knockouts that resemble the letter C.

While I am out today I will see if I can find one and post a shot of it.

Wayne
--
Madness takes its toll, please have exact change ready…


Nick_L
Premium
join:2003-01-22
Pittsburgh, PA

Thanks for the education. I've not seen those (that I'm aware of, anyway).



49528867
Premium
join:2010-04-16
Fort Lauderdale, FL
kudos:3

said by Nick_L:

Thanks for the education. I've not seen those (that I'm aware of, anyway).

I didn't have a chance to locate one today but this is a catalog shot of some.




Wayne
--
Madness takes its toll, please have exact change ready…


Nick_L
Premium
join:2003-01-22
Pittsburgh, PA

Thanks.