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Electrical Vehicle Chargers - No Diversity?

Apostolos

Good afternoon

I have a question to address to more experienced engineers in here about the load calculations around EVCs

Its clearly stated in BS7671 that no diversity should be applied to an EVC

This is a bit weird to me as to the ramifications it has

So, assuming we have a TPN 32A EVC, this means you cant apply diversity and feed it with a 20A MCB. It should always be a 32A MCB

All good

What happens in case you have a DB feeding 5 off these chargers?

Assuming you do not have a load management facility between the 5 chargers, does the 'no diversity' mean I have to assume a DB charged with 5 x 32 = 160A load????

And protect it with 160A, and install a cable for 160A etc etc etc?

Is this what no diversity means for the EVCs?

Always assuming you do not have a load management system installed in the EVCs

Thanks

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  • 0
    Apostolos said:
    So, assuming we have a TPN 32A EVC, this means you cant apply diversity and feed it with a 20A MCB. It should always be a 32A MCB

    That's not diversity.

    Apostolos said:
    Assuming you do not have a load management facility between the 5 chargers, does the 'no diversity' mean I have to assume a DB charged with 5 x 32 = 160A load????

    Correct. No diversity means that you assume full load rather than only 3 in use at any one time (96 A) or 5 in use, but drawing less than the full 32 A load.

    Note that not all EVs can use all 3 phases, and some which can use 3 phases cannot draw as much as 32 A per phase.

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  • 0
    Apostolos said:
    So, assuming we have a TPN 32A EVC, this means you cant apply diversity and feed it with a 20A MCB. It should always be a 32A MCB

    That's not diversity.

    Apostolos said:
    Assuming you do not have a load management facility between the 5 chargers, does the 'no diversity' mean I have to assume a DB charged with 5 x 32 = 160A load????

    Correct. No diversity means that you assume full load rather than only 3 in use at any one time (96 A) or 5 in use, but drawing less than the full 32 A load.

    Note that not all EVs can use all 3 phases, and some which can use 3 phases cannot draw as much as 32 A per phase.

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