I hired a new EC about a month ago from recommendation from another Cell Phone company. I awarded him with a contract to install the electrical in six cell towers sires that I was building in his area to try him out.

Since these are rural sites and for a phone company, there was no permit required, so I inspected each site after work is completed, blah, blah blah.

I went to the first site and was impressed with the work, very strict attention to workmanship. Then I went out to the AC service frame to inspect meter and disconnect switch. I noticed the 2/0 GEC was missing from disconnect switch, but the PVC was there for it. I found that strange, as I knew the cable was in the specs, and I had seen it there stubbed up, as it is part of a huge grounding ring/grid. So I dug into the crush-n-run and found it buried. OK, maybe a minor mistake or oversight took note for punch-list.

Went to the next site, same thing, buried GEC. OK now I am seeing a pattern. Third site same thing, now I am pissed.

Went to the forth site where EC was working to confront him. He stated he did that at all cell sites for added lightning protection and so he could work the system bare handed at a later time if need be.

Fired him on the spot, reported him to AR State licensing board, and to the engineers at the cell phone company that recommended him to me. I understand that Verizon checked his worked and found the same thing. They are suing to cover the price of re-work at multiple sites, and solved the mystery of why the were constantly loosing rectifiers and HVAC.

Sorry to vent just had to get it off my chest, as I can’t talk about it around work, too embarrassing.

Dereck, good for you, these type contractors take work from the others who are willing to adhere to the contract documents.

It's amazing how many people I've talked to that think their way overides specifications.

The bottom line is the contractor that would bid to the spec looses a good contract, the owner gets a substandard installation, the designer is frustrated as you are here, the offending contractor looses money if he is forced to redo the work, so overall these people cause all to loose.

I guess I'm drifting into a vent myself so I'll stop here.

Roger

I can't figure off of the top of my head how the GEC would cause you to lose your HVAC

electure, tower sites are magnets for lightning strikes and the controllers get taken out.

I'm not familiar with this installation, but from your description, the wire was there, but he didn't make the connection? So now he's lost his reputation, probably his bread & butter work...because he thought he knew better???

I guess he knows better now.

Dave

... for added lightning protection and so he could work the system bare handed

Even though you had the urge to strangle him I still would want to hear his explanation for that one!

-Hal

Hal, I did get his explanation. The meter service and disconnect are installed on an “H” frame inside the fenced perimeter but away from the building. It is a typical 200-amp single phase service. The “H” frame is cad welded to the ground grid, and the EGC uses a bonding bushing on the enclosure. Feeders leave the “H” frame, all 4/0 copper including EGC and go underground to the building main panel. The main panel ground bus has a supplemental connection to the grid with a 2/0 cable. His explanation was since the “H” frame was bonded to the grid, and the ground bus in the main panel was bonded to the grid, another connection at the service would create loop and was not needed. He said it violated the single point ground window I created in the radio building.

I was really disappointed, his workmanship was incredible. If he hadn’t insulted my intelligence and re-worked the GEC at all sites, I would have used him again on a short leash. I can’t understand how he obtained a Masters liscense.

So then, as he had it, the bond of the service to the ground grid was through the frame bond (strap/screw/lug etc.) and then again through the EGC via the main panel ground bus lug?

I can't blame you for firing him, if he thought he had a better idea he should have put it past you, etc..... all kinds of wrong on many levels on his part, one of which I would bet was his attitude (I am guessing because you sound pretty peeved, and an arrogant jerk can really set off fuses).

But (and my intelligence is the only one intended to be insulted here) would the service, although improperly grounded, still have had adequate ground potential? I know I am missing something. Was the lightning path too high of impedance? Was lightning and gradient voltage being routed through the main panel?

This might get into lightning protection, which as far as I'm concerned is a different cousin of the field than the one I'm in.

I'm way over my head here- I can't even fix my car's antenna- but:
-A 4/0 wire has to be a lot more conductive than any incidental metal connections; and,
-I'd reallt think long and hard before I ignore something that large and pricey.

I've had my share of stupid specs, but those are always issues to discuss with the customer- not to ignore and bury!

I'm only sort of guessing here, but wouldn't the Earthing system for the Tower be a Grid system, made up of bare copper?.
Also, running a bare wire under the ground here is a pretty acceptable way of effecting an Earth, you only require a certain resistance.

The GEC is required by 250.24 to be connected to the service disconnect. That's what this guy didn't do.

The supplemental ground from the sub panel ground bus in the building to the grid is not required by the NEC, but is a design issue that I'm sure has been proven to be beneficial in all of these installations else it wouldn't be required.

-Hal

Trumpy asked; “but wouldn't the Earthing system for the Tower be a Grid system, made up of bare copper?

Yes. FWIW I used the word grid only to convey what is there is beyond what the code requires. It is actually a combination of three ring/rod systems. One around the building, tower, and fence line. The rings are interconnected by radial/rods, and the radials extend out several hundred feet to each tower guy support and any pad used like the “H” frame for AC service. All the ring/radials is 2/0 stranded tinned copper. There is also a grid laid between the tower and building made of a pre-manufactured #6 AWG on 6-inch center welded at the grid intersection. Plus there is a chemical rod between the tower and building located at the base of the building where all the coaxes and services enter the building. Everything is CAD welded together.

On the building the is a copper bulkhead located on the tower side. This bulkhead is bonded to the ring/chem-rod with three 6-inch wide copper straps. The bulkhead is where all the coaxes, alarms, Telco. Etc enter the building. Where these cables pass through the bulkhead, we have special surge arrestors made by PolyPhaser that mount in the hole in the bulkhead. The Bulkhead also has a “Z” shaped structure that forms a large ground buss for us to use to bond all the equipment in a radial/parallel fashion called a Master Ground Bar (MGB).

All the radio/transport equipment, rectifiers/batteries, cable trays, conduit, AC main panel, everything is electrically isolated from incidental contact with the floor, walls and ceiling. In other words it is like everything is floating in thin air. Then the AC ECG bus, DC return bus, all equipment frames, raceways, etc is bonded to the MGB in a radial fashion. This is what forms a isolated single point ground. All this effort and expense is to keep any lightning or outside fault current from flowing through the equipment causing potential differences. It works great providing there is no corruption of the isolation and everything is bonded to a single point less than 3-feet between any two points.

Probable more than some of you want to know, but thought I would share for those who are curious why we go to the trouble.

That would be for me. thanks. I'd love to see a print too, but I know that's not a practical request.

[This message has been edited by Jps1006 (edited 11-04-2004).]

I'd love to see some pictures of this system!

Dave

Hi,
Sounds kind of harsh to me..maybe you over reacted? You sound hard to work for.

Why did you not offer him a chance to correct the mistake at his expense?

-regards

Mustang

Why did he run the empty PVC to the bottom of the disconnect if he buried the wire in the gravel? Sounds like he was being a bit deceptive, no?

-Hal

Mustangelectric, I would have let him corrected his mistake if he bit the bullet and said something like I screwed up or overlooked it. But here are the facts:
1. He installed the PVC for the GEC but did not run it. Indicates to me deception on his part.
2. He installed all the ground work, rods/radials, etc so he knew it was there, clearly shown on prints with PVC, again indicating deception.
3. Rolled the GEC up and buried it after I inspected the site before everything was covered over.
4. Willingly, knowingly violated code by his own confession
5. Implied that other electrical engineers and I didn’t know jack about electrical grounding.

Just too many strikes to overlook. Perhaps I am hard to work for, at least the first time around until I am confident, then I pretty much let my contractors have free run at things. Like I said his workmanship otherwise was excellent. If he had said I screwed up, have it fixed ASAP, he would have had all my work in his area.

Hi,
You wrote...

"I went to the first site and was impressed with the work, very strict attention to workmanship."

"Went to the forth site where EC was working to confront him. He stated he did that at all cell sites for added lightning protection and so he could work the system bare handed at a later time if need be.

Fired him on the spot, reported him to AR State licensing board, and to the engineers at the cell phone company that recommended him to me."

I am not really taking anyones side here but just reviewing the original post it sounds to me like you were gunning for this fellow.

It appears that you and he had a disagreement based on the plans. If you had a contract how do you fire someone without legal ramifications? Myself i would have just sent this out to my attorney.

If I have the same set of plans that everyone else has then I do not build it the way it is shown then I need an explanation as to why it is not like the plans. The Architect or engineer or project manager may come and question me as to why I am not building to plan but usually there is a meeting of the minds..if I am wrong and someone points that out then I would gladly correct any problems. I bet this fellow would have done the same thing.

I do not think you had any right to file all these complaints with the Arkansas Dept of labor...I know them down there and I doubt that this was anything they would act on.

It sounds to me like you flew off the handle and went for blood.

Maybe try and take two and think it through next time..

I did not see any comments you made that would warrant all the complaints you filed.

Atthe most this warranted a meeting or a little chat with the PM and the EC.

You started out praising the guys work.

I always prefer negotiations prior to legal action.

Just my two cents.

-regards

Mustang

Mustang, seeing how Dereck is the engineer of record, and considering this guys obvious deception, (apparent by the pains he took in hiding what he did) I don't think his attorney would recommend he try to go anywhere with this.

Well on second thought, the attorney would make money no matter what happened, so I'm probably wrong here.


Roger

There's also the possibility that the designer is questioned about his design because of the damage to this equiptment, when, in fact, the equiptment is being damaged because the design isn't followed.

Dave

Hi,
I did not see any deception on the EC's part but maybe I missed something. Are you talking about the fact that he buried the cable? I did not see that as decpetion...maybe I read it wrong.. but I will just butt out so I do not rile anybody.

regards

Mustang

Dave, I hadn't thought about that, but it's an excellent point.

Roger

Mustang, you are not getting me riled up so please feel free to speak.

The EC intentionally buried the GEC, installed the PVC and left it empty. He told me straight up he didn't install the GEC for me or any other Cell companies because he didn't feel we engineers knew what we were doing.

Look at it another way, suppose I had to pull a permit, and the AHJ caught it before I did, seen the plans, then heard the excuse. Red tag period, and would probable remembered his name.

Roger is correct, I am the engineer plus the PM, estimator, and inspector. So I am fairly familiar with the details.

Edited to correct spelling



[This message has been edited by dereckbc (edited 11-04-2004).]

Communications work has special design requirements, and this is where the EC has to follow the plans as designed, if he finds any condition, that appears improper, it is best to document the problem and submit it to the Engineer in charge for review, but don't make any changes on your own.
Common bus system for communications , may differ depending on the equipment configuration power requirements and frequency.
The engineers, that work in these fields know all the special requirements, and for him to comment that the engineers din't know jack about grounding din't help his cause, If he thought there was a problem with the grounding, he should have brought it to the engineers attention, and discussed it with him, not just make his own changes.