Balanced current standard

[Dragonclaw]

Is there a USA or European standard to be followed in order to prevent an unbalance of current in a building installation?
I have a "lot" of signle phase electrical computer equipment to connect to a 220VAC/240VAC utility supply. Each device consumes 300W of input power and I need to install 500 devices. (150KW). If I install all 500 devices onto one of my signle phase lines, then have I broken any building installation requirements?

 

[buzzp]

I don't believe you will violate any codes but you will likely violate good design. Assuming the original loads were balanced well it would be a good idea to spread the load around to maintain the balance. Otherwise the result could be an unbalance, causing problems with 3 phase equipment or even single phase equiment for that matter. I am assuming the switchgear, cables, etc.. are sized to handle the additional load but I would certainly verify this. Your additional load could violate some standards (namely the NEC) by adding this load and having too small of wire and/or switchgear. Any unbalance discussions, at least as far as the NEC is concerned, are only recommendations and not mandatory.

 

[Dragonclaw]

The wire gauge and switch gear are all rated to handle this level of load. However, I do not know of a permissible level of unbalance. Is there a standard or rule (I've heard of a 10% figure, but am unaware of where this comes from)

 

[rbulsara]

Good design practice and commen sense are NOT covered by Codes.

Codes only cares for saftey not functionality. Meeting Code is a necessary (statutary) requirement but not a sufficient requirement. For example, a reversed wired motor may meet the Code but will not do the job its supposed to do.

So, use you good judgement. The 10% figure is a well accepted figure, based on sound judgement of people who had the experience before , it is worth something.