I've purchased a wall mounting enclosure by ABB (serie Europa), and in the manual they recommend special designed terminal bars ABB 12494 for the enclosure. I can't figure out if I need TWO of this bars, one for neutral and one for protective earthing or I've to get just one actually and use it for both? Please help me to figure this out.


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Recommended terminal bar: enter image description here


First of all a warning. If you are not sure with working on mains then stay away from it. Furthermore for safety always remove the power from the incomming line by opening the corresponding breaker.

If you look good then you can see that the connective bar is separated into 2 parts. One part for (P)rotective (E)earth (yellow/green) and the other part for (N)eutral (blue).

You can use a insulated bar any way you like. In this kind of connection boxes a non insulated bar should only be used for PE(green/yellow) connections.

  • thank you very much for the warning. I would involve specialist for the assembly, just picking the right stuff to buy first. Cause assembly will take short amount of time, and I want to take my time to pick right parts by myself. The bar I illustrated is insulated, right? And by 2 parts you mean 5 holes separated on the right? So to speak this 5 holes can be PE and the left side is N, right? – Mike Mar 26 '17 at 14:30
  • That is correct – Decapod Mar 26 '17 at 14:31

Generally speaking, the neutral (grounded) conductors are bonded directly to the protective earth (grounding) conductors ONLY at the the service entrance for the building. This is the only panel in which you can use a single continuous bar for both. In all other (sub) panels, you must use separate bars, and the neutral bar must be insulated from the case.

However, note that the assembly you have pictured actually contains two separate bars.

  • In many situations the (N)eutral and the PE are NOT connected together at the service entrance of the building. The way it is done depends on the applied system. Ask your electric supply companie for more information. – Decapod Mar 26 '17 at 16:47

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