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

1 edit

1 recommendation

The most screwed up electrical work I have ever seen.

This is a natural gas CNG pumping station, think final storage pressures of 3600 psi, well their original pump took a dump and another one had to be placed.










You gotta love when plumbers re-do explosion proof electrical work.

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

iknow
Premium
join:2012-03-25

Re: The most electrical mis-installation I have ever seen.

it looks like they didn't put the new pump in yet!. so that's the way it was originally?



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

No, thats the "new" pump you are looking at.

Wayne



tp0d
yabbazooie
Premium
join:2001-02-13
Carnegie, PA
kudos:5

im guessin they had to cut the conduit to remove the pump or motor?

whats the issue with a union in the middle? i guess it could interrupt ground, but there should be a dedicated ground anyways, and the threads on each pull fitting could eventually become corroded, and hamper ground as well..

-j
--
if it aint broke, tweak it!!
currently on FiOS (kick aZZ!)



Raphion

join:2000-10-14
Samsara
reply to 49528867

Hard to believe that's 'new'... looks like something that's been on it's last legs for the last decade or two haha Scary looking really.


rfnut
Premium
join:2002-04-27
Fisher, IL
kudos:2
reply to 49528867

I always use teflon tape. Pipe dope is too messy for electrical work.



nunya
Premium,MVM
join:2000-12-23
O Fallon, MO
kudos:12
reply to 49528867

Wow. Just wow.



AnonEEMouse

@bhn.net
reply to 49528867

Hey, gotta give them credit, at least they used Rectorseal on the pipe threads!

Doesn't this sort of thing have to be inspected?

Reminds me of something I wish I had pictures of, not as deadly but pretty ridiculous. I was tracing upstream noise on a node, we had finally got it pinned to one block, but it was intermittent, so pretty hard to track. At this point we were trying to narrow down where the problem was when I noticed a pretty good sized HF antenna on one house, so naturally I checked there first. I was walking back to the pole and at the same time I noticed the house had a no DMARC, but had (white!) cable running from the pole into the roof with a P-TRAP being used as a weatherhead and regular PVC going into the attic! he had even went through the trouble of putting a lead boot on the abortion! Get up to the pole, lo and behold what I suspected was true, theft of service. To top it all off, he even broke one port of the tap completely off trying to get the locking F terminator off! Needless to say, once the tap was replaced and his clusterf&ck disconnected, the noise went away.

Never ceases to amaze me the stuff I see "professionals" and DIY'ers do...



nunya
Premium,MVM
join:2000-12-23
O Fallon, MO
kudos:12
Reviews:
·Charter
·voip.ms
·surpasshosting
reply to tp0d

That's a Class 1 Division 1 location. The LB's and union obviously do not belong in this picture.
They essentially turned the $2,000 explosion-proof control box into a potential "bomb".
I know they are explosion-proof from the outside. Not to sure about the inside.
--
If someone refers to herself / himself as a "guru", they probably aren't.



tp0d
yabbazooie
Premium
join:2001-02-13
Carnegie, PA
kudos:5

1 edit

yea it does look like they added the 90° pull boxes (LB's?)

surprised the gas co let someone like this work on their stuff.. hmm

-j
--
if it aint broke, tweak it!!
currently on FiOS (kick aZZ!)


sk1939
Premium
join:2010-10-23
Mclean, VA
kudos:10
Reviews:
·T-Mobile US
·Verizon FiOS

said by tp0d:

yea it does look like they added the 90° pull boxes (LB's?)

surprised the gas co let someone like this work on their stuff.. hmm

-j

Low bidders generally win contracts.

Badonkadonk
Premium
join:2000-12-17
Naperville, IL
kudos:5

1 recommendation

reply to 49528867

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

It's gotta be asked and I'm willing to take the lumps.

So, what's exactly wrong with it?



leibold
Premium,MVM
join:2002-07-09
Sunnyvale, CA
kudos:10
Reviews:
·SONIC.NET

said by Badonkadonk:

So, what's exactly wrong with it?

The metallic conduit is supposed to provide a continuous safety ground. Using teflon tape on the conduit joints prevents electrical contact. This in turn allows parts of the conduit to become electrically charged possibly leading to sparks from one part of the conduit to another.
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Got some spare cpu cycles ? Join Team Helix or Team Starfire!


The Pig
I know you want to be me
Premium
join:2009-09-11
reply to 49528867

I'm with Goober What does the pipe have to do with the wires inside it?
Unless water is getting in the pipe I don't see a problem!
Wasn't the pump inspected after it was installed by an inspector?
Are you saying the pipe is a ground?



leibold
Premium,MVM
join:2002-07-09
Sunnyvale, CA
kudos:10
Reviews:
·SONIC.NET

said by The Pig:

Are you saying the pipe is a ground?

The other way around. All exposed metallic surfaces must be bonded to the equipment grounding conductor.

In other words, every section of the pipe must be grounded but the teflon tape prevents that (isolating each section).
--
Got some spare cpu cycles ? Join Team Helix or Team Starfire!

Badonkadonk
Premium
join:2000-12-17
Naperville, IL
kudos:5

Perfect. Thanks.


garys_2k
Premium
join:2004-05-07
Farmington, MI

1 edit
reply to Badonkadonk

Also, this application requires "explosion proof" fittings. Those standard LB's do not have the required ratings.



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

said by leibold:

said by Badonkadonk:

So, what's exactly wrong with it?

The metallic conduit is supposed to provide a continuous safety ground. Using teflon tape on the conduit joints prevents electrical contact. This in turn allows parts of the conduit to become electrically charged possibly leading to sparks from one part of the conduit to another.

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.


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

4 recommendations

reply to Badonkadonk

said by Badonkadonk:

So, what's exactly wrong with it?

Good question and no lumps for you, as Nunya already pointed out this is a "class/division" area which in layman’s terns means an area where something flammable may be present and electrical equipment utilized in that area must be designed to be explosion proof.

Now explosion proof doesn’t mean the equipment utilized must be able to resist an explosion, it means should an explosion occur within the equipment the flame wall from the explosion will be contained within the equipment and not continued out of it.

So lets start with the big one the control cabinet, that cabinet contains pressure switches which monitor the input pressure of the compressor about 4 psi and another cycles the compressor based on output pressure which is about 3600 psi, it also contains a contactor and some low voltage control relays.

Now lets say within this finely tuned and maintained system a pressure control switch develops a pin hole leak and that leak beings to fill the control cabinet with natural gas which in turn mixes wit the air already in the cabinet, then someone connects their CNG vehicle to the device outside and drops the storage pressure as the vehicle is filled, the output pressure sensor sensing the lower pressure closes kicking in the motor contactor either of which can produce a spark igniting the gas air mixture within the cabinet.

Now if this job was done properly that explosion would be contained within the cabinet and the connected conduit.

But this job was redone by some jacklegs and what will happen is the plastic rain-tite run from the cabinet to the motor and a control conduit will blow off and that’s good as hopefully doing so will drop the pressures a bit, because if not those LB’s will explode violently and if that pipe between them nails one of those stainless steel lines on it’s way out of there it will unleash a 3600 psi dragon breath.

Note the LB’s in shot 3 are those two grey boxes one above the cabinet and the other to the right changing the direction of the large pipe from vertical to horizontal.

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

Badonkadonk
Premium
join:2000-12-17
Naperville, IL
kudos:5

Very nice explanation! Thanks



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

1 recommendation

reply to Jack_in_VA

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:1
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!