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Joined: Aug 2001
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Thanks to Johno12345 for the following: We have just changed the lights in the cellar at work, I was looking at the meter and noticed something worrying...
Ignore the fact that the cutout has been on fire (There used to be a lead one that got crushed) The earth cable that is loose on the right goes to the gas service pipe before the meter and then the water main. The earth on the left goes to the switch fuse which feeds a Federal Electric Stab-Lok panel upstairs. [This message has been edited by pauluk (edited 05-26-2006).]
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That last picture, where the bonding conductors are all terminated, Am I wrong or are they TWO separate blocks??? From what I see they aren't event touching, and the way its described and the way I see it, the panel located upstairs is technically NOT bonded to earth is it??
A.D
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Corect, those earth blocks are totally seperate! The only earth is to the gas pipe (pre gas meter) and to the water main. It has been like this since the building was renovated in 1984. It looks like someone has positioned them like that to look like one earth block. I think we are lucky here that there have been no injuries.
It always makes me wonder because someone has done that knowingly - how can they sleep?
Anyway, it was all sorted about an hour later. we just hope out Stab-Lok panel doesnt go the way of the American ones!
I took my time, I hurried up, The choice was mine, I didn't think enough
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Aren't Earth conductors required to be terminated in a continuous non-ferrous busbar?.
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shows that when you undertake a periodic inspection report you must look closely at even the simpilist of items, I trust you have recified the terminal as this could be seriously dangerous.
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If there are any boilers, pumps, or similar equipment in the building, then there was probably some sort of earth via their cord's earth conductor and back via the water and/or gas pipes. I wouldn't have wanted to rely upon the small earth in those cords to clear a ground fault from the main panel though!
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Joined: Dec 2005
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That earth bar, block is shocking, those are two separate blocks and are NOT providing any continuous earth protection.
What size is the earth here? It looks like 25 or 35 mm² . Quite a bit of corrosion too on the RHS earth.
The polyphase meter is that a GEC E43B3B, 2 rate series, 100 Amps ?
The product of rotation, excitation and flux produces electricty.
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My comment about the busbar, stems from the need to have all equipment and it's Earthed parts to be at the same potential. This could be why it is called Equi-potential Bonding. Considering that there is a Gas line and so forth that is supposed to be effectively Bonded and Earthed, if that happened here, some Inspector would be for the Chopping Block. In this case of negligence I'd be the first to blow the whistle!.
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The earth is 25mm and the supply is 35mm, it is 100A, not sure of the meter type. All i noted was that it was singed slightly. There is a boiler and A/C system It used to have a commercial kitchen for the staff canteen that was all steel I think it was bonded to the spare terminal. It is the only thing we have found so far in this building and we are suprised as it all seems to have been done really well.
Are Federal Electric Stab-Lok panels OK? just imagine if they were of the no-trip kind, live kitchen and taps!
incidentally, we were logging voltage swings on a UPS from about 218V to 280V, we had the panel and supply checked and it all seems ok, I wonder if the poor earth might have confused the UPS.
I took my time, I hurried up, The choice was mine, I didn't think enough
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Johno12345: Can you get a picture or two of that FPE panel by chance??? I would like to see how they compare to the ones over here if possible....
A.D
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