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Posted By Topic: Switchboard Replacements continued

blair
Nov 03 2013 12:19

Hi There, thought at plus 40 messages it was time to start a new thread.
As previously discussed there is a difference of opinion wether a replacement board ie low or high risk.
My question is if the original board had both the main earth and nuetral under the same stud what do you do.
If you put the same condition tegether in the new board is it low risk and ESC and if you separate the main earth onto the new bar does it then become high risk and require inspection and COC.

I personally always get it inspected anyway and separate out the earth wire to the earth bar.
   

Saturn
Nov 03 2013 15:44

Regarding earthing, seldom do I find the earthing system of an existing installation complies, even to what was originally acceptable.Over time the original pipework has been altered,The main pipe system on the network is plastic. The original pipework has often been replaced or parts of with plastic, etc,etc. So in most cases an inspection is required.
   

DougP
Nov 03 2013 16:52

@Blair.
Obviously you need to do any work to the current regulations and standards, even if it is low risk maintenance or replacement.

As has been determined in the other thread, replacement of a fitting (N&E bar) is low risk.

   

DougP
Nov 03 2013 17:21

And when replacing a neutral and earth bar, don’t assume that just because you have the main switch turned off, that the whole installation including the neutrals can’t be live.

I had one of my own properties, where some tenant in the past had connected the feed to one fuse, to the active feed on the ripple relay. Disconnecting the neutrals and found the one live one.

I guess you could remove all the fuses, and test if any still are still live. Or do a better visual inspection of the connections. Or test all outgoing actives with a volt stick type of thing.

I guess the most reliable way would be to remove the main neutral and earth (while expecting the bar to then be live), and test the bar to an independent earth?

Does anyone have any better solutions apart from getting a disconnect? Or is a disconnect the preferred option?

   

mowgli
Nov 03 2013 18:52

@Blair, what you describe doesn\'t sound like a straight forward replacement. Re-labelling the combined earth/neutral bar to be a dedicated neutral bar might go under the radar. Installing a new earth bar and MEN link where there wasn\'t one previously cannot possibly be maintenance or replacement.
   

blair
Nov 03 2013 19:52

The original bar is still an earth nuetral bar with the MEN link. It is just that the main earth and nuetral were installed under the same stud which was very common in the eighties and beyond. Now we like to see the main earth on the earth bar and in its own terminal. It is still the main earth and main nuetral connections that are getting moved to a new switchboard and so I believe should be inspected despite what the other thread believed as it could still be re connected faulty or loose or incorrect. The inspector gives a second look at the new work. That is the only part I get the inspector to sign off on as I give COC from myself for all other work on board.
   

DougP
Nov 03 2013 20:13

Fair enough Blair.

When doing this type of work, the network will be isolating the installation for you in any case. So what I usually do is arrange this with an inspector, and they inspect prior to re-livening.

Often when re-livening, I only have main earth, neutral, MEN link, and the main active connected to the main switch. This is all they need to inspect.

I generally don’t try and do “as little as possible” on the jobs. If it’s old stuff, it’s a lot easier just to replace the whole lot with a new board. If the customers just want to do it as cheap as they can, they can ask someone else to do it.