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A customer is building a new industrial unit on a new site as a woodworking shop. He asked me for help filling out the SSE supply request forms, but a few of the questions have me stumped:
What we want is a 3 phase supply up to 100A per phase, with a conventional 3 phase meter, so tails from supply fuses to meter, and tails from meter straight into 3 phase board.
How do I translate that simple requirement on to the form?
Metering: tick box to choose HH (Half Hourly) or NHH (not Half hourly) I don't have a clue what that means.
Meter type: CT (current transformer) of WC (Whole current) Well CT metering is for large current installs so I assume my "normal" meter is WC?
Also what KVA requirement should we put? He's not going to use much, probably no more than 2 machines at a time plus lighting and office stuff, but I don't want to under spec the supply. So my inclination is to ask for a "proper" 100A supply, i.e that would be 69KVA if all 3 phases were loaded to 100A. I think what I'm getting at here is the charges for installing the supply go in bands, i.e for domestic it's "up to 16KVA" or "over 16KVA" so does anyone know the equivalent bands for a 3 phase supply?
He's trying to get an adequate supply for as cheap as possible. He's even considering a 23KVA single phase supply and using a rotary single phase to 3 phase converter. I'm doing my best to persuade him that an industrial unit of 400 square meters really should have a 3 phase Supply.
I think the confusion is caused by the fact one form covers anything from a simple 1 phase LV 16KVA supply, up to a HV supply feeding an aluminium smelter.
Also, looking at the forms he has, it seems industrial users are getting charged high prices for their electricity, the cheapest tariff was listing 21p per unit, almost double the domestic rate. Ouch.
What we want is a 3 phase supply up to 100A per phase, with a conventional 3 phase meter, so tails from supply fuses to meter, and tails from meter straight into 3 phase board.
How do I translate that simple requirement on to the form?
Metering: tick box to choose HH (Half Hourly) or NHH (not Half hourly) I don't have a clue what that means.
Meter type: CT (current transformer) of WC (Whole current) Well CT metering is for large current installs so I assume my "normal" meter is WC?
Also what KVA requirement should we put? He's not going to use much, probably no more than 2 machines at a time plus lighting and office stuff, but I don't want to under spec the supply. So my inclination is to ask for a "proper" 100A supply, i.e that would be 69KVA if all 3 phases were loaded to 100A. I think what I'm getting at here is the charges for installing the supply go in bands, i.e for domestic it's "up to 16KVA" or "over 16KVA" so does anyone know the equivalent bands for a 3 phase supply?
He's trying to get an adequate supply for as cheap as possible. He's even considering a 23KVA single phase supply and using a rotary single phase to 3 phase converter. I'm doing my best to persuade him that an industrial unit of 400 square meters really should have a 3 phase Supply.
I think the confusion is caused by the fact one form covers anything from a simple 1 phase LV 16KVA supply, up to a HV supply feeding an aluminium smelter.
Also, looking at the forms he has, it seems industrial users are getting charged high prices for their electricity, the cheapest tariff was listing 21p per unit, almost double the domestic rate. Ouch.
