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Triple phase switchboard

Jacklpthompson

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Joined
Oct 13, 2025
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Hello,

I’m looking at getting a second 7kw EV charger and I understand it needs triple phase to charge both cars at 7kw at the same time. Does my switchboard look to have triple phase please? If not, how much roughly would it cost to add? Would the EV fitter be able to do it? Many thanks
 

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3-phase residential is rare here unless you’re in a commercial space. Most EV setups just split the load across separate 40A or 50A circuits. Two 7 kW chargers will pull roughly 60A combined, so it’s more about your main service capacity than phases.
 
Hello,

I’m looking at getting a second 7kw EV charger and I understand it needs triple phase to charge both cars at 7kw at the same time. Does my switchboard look to have triple phase please? If not, how much roughly would it cost to add? Would the EV fitter be able to do it? Many thanks
That's a 100 amp, single phase load center, Jack.
Paul
 
You will need to apply to your DNO. They will want a load assessment of your current and proposed loadings and then they can tell you your options and quote accordingly
 
@Jacklpthompson adding three phase is a major undertaking, and the cost isn't just the electrician's time, it's mainly the utility company digging up and installing the new service line and meter. It could easily run $5000 to $15000+ depending on your area's infrastructure. Start by calling your utility provider, not the EV fitter
 
The load center in your photo is in the U.K. Is that correct? Perhaps there is a second, less expensive, option for you:

Ask the utility for a separate meter for EV charging.
Some offer lower rates if done that way. Where I live (in the U.S.), if one asks, the utility will add a separate meter. the load is not off your existing 100 amp load center. For a neighbor I helped who had 100 amp service, the utility upgraded her service to accommodate 2 EV. No cost to her and lower kW rate.

A third option is that you can upgrade your existing single phase service to a higher amperage single phase service. No need to change to 3-phase. (Unless it is inexpensive in the UK to do that. Here, if a residence wants 3-phase they have to pay for the pad mount transformer and CT metering. )
 
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