Changeover Switch

Continue to say 4-pole, as you have already identified. It has to be double throw, since it is connecting to two sources (unless it is two separate but mechanically interlocked switches). ABB is reputable.

HI

If I am not mistaken it is a ATS which you are talking about .The rating is according to the calculations from LV side .ABB in Europe USA is best .ABB middle east no comments --------------------------------------------------------------------------------

Changeover switch = Transfer switch

Some part of the world, transfer switch is called changeover switch.

Transfer switch (or changeover switch) must be double throw – you don't need to mention it.

About pole, see the recent thread http://cr4.globalspec.com/thread/53968/Domestic-Installation. It has pretty much detail about what you need. You can select either TPN or 4P based on the guideline provided in this thread.

- MS

Over here in the land of the NEC, we describe it as the following;

If you operate it by hand, it is identified as a "Manual Transfer Switch"

If it is automatic (no human involvement) it is identified as an "Automatic Transfer Switch" or "ATS"

As far as number of poles, on construction drawings I see daily it is described as "single phase" or "three phase".

Therefore, if a given switch is rated at 400A, three phase and automatic, it would be identified as a "400A - Three Phase ATS"