Can you post a clearer shot of the drawing or explain the problem in words - I cannot see what you are indicating. Why is there a swing link in the earth at all ?  Normally if a bolted earth needs to be removed for testing, it can be unbolted. A swing link is more like a switch, in that there is an expectation it may be left in the open condition -is this true?

Is there a description of the test that requires the link to be open ?

Looks like the earth bar has been shortened or is the wrong type.


Usualy the means of earthing ( the earthing conductor) is connected before the earth link say stud 1. The removable link is on studs 2 and 3. Every other bonding conductor or CPC is connected to studs 4 to N. That way all conductors stay permanently connected when the test link is removed to carry out a Ze test.


New earth bar required?

Hi Mapj1 -  hopefully this helps.


They have put the main connection after the disconnecting link which look wrong.


Surely the main one would be on the first stud and then all the others would be after the disconnecting link.


On their drawing revision they specifically said that they had moved the main connection from the other side of the link.




Don't have much other information - just little snippets.

Hi John


Yeah, what I was thinking - looks like the link has been installed wrong way round - to be spun around and the earth connected to the first stud then.


I just thought it weird they specifically made the change on the drawing - to clarify the drawing is by the installers own designer

I'm with Mike - it does sound rather like someone has decided that they don't really need a disconnecting link on the earth bar and would prefer the additional reliability of having everything solidly bolted together.


It may be that a removable link for testing is only required at the main earth terminals - and any anciliary ones are to be treated as simple terminals/bars (but if they've already been purchased/installed with disconnecting links the pragmatic if rather untidy solution is just to make all the connections on the same side).


Just my guess though.


   - Andy.

Thanks Andy, I will try and get a contact with someone to verify the reasons. It was just the fact that the design drawing had the funny arrangement that confused me.

Thank you for the revised drawing -  so long as the link is fitted, electrically it does not matter - it's only purpose is to act as a ssort of switch that needs tools (but cannot be locked) to isolate the end terminal. In this case that can be done just as well, as you have to have the spanners anyway, by undoing the end bolt.  Swing links make a lot of sense when you have chunky earth cables or lightning conductor style strips that are rigid and cannot be sprung out of the way - its the sort of thing you see in big buildings with installations of a few hundred amps and up. If the wire is just 10mm2 or whatever, you'd not normally expect to see a link, as it is just another thing to shake loose, or for the installer to forget to tighten. They may have had quality control problems in that area, and decided it is safer to not use the link,

ME1999


No point in having the bus bar shown and specified with a disconnecting link if the link serves no purpose. 


MAPJ


I have somewhere on my hard disk a photo showing a padlock through the link to prevent it being removed by an unauthorised person. If I can find it I will post it here.

It doesn't make much difference to someone with a spanner or pair of grips, they can disconnect it wherever it's connected on that bar.