EV charging point installation

Home EV charger installation and your incoming supply

A 7kW charge point pulls around thirty two amps continuously, which is more than almost anything else in a house and it does it for hours at a stretch. So the first job is a proper look at the incoming supply, the main fuse rating and the state of the existing consumer unit. Plenty of older properties in Lincolnshire still have a smaller cutout than people assume, and once you add a shower, an electric oven and a car, the arithmetic gets tight.

Where headroom is short, load management is the answer instead of a smaller charger. A CT clamp on the incoming tails lets the charge point throttle itself when the rest of the house is drawing hard, then ramp back up when the kettle goes off. The car still charges overnight, it simply works around everything else. That is usually far cheaper than applying for a supply upgrade and, on most drives, invisible in day to day use.

The charger gets a dedicated circuit and its own protective device, never a spur off something convenient. Cable size and route are worked out for the actual run length and installation method, because a long run down a garden to a detached garage is a different calculation from a unit on the wall beside the meter. Get that wrong and the charger will either trip or sit there derating for the next ten years.

Earthing arrangements and open PEN protection

This is the part of EV work that catches people out. On a PME supply, a broken neutral out in the network can lift the whole earthing system to a dangerous potential, and outdoors, where you are touching a car with your feet on wet ground, that matters far more than it does indoors. The wiring regulations require the risk to be managed properly, and there is more than one accepted way of doing it.

Most modern charge points include open PEN detection, which disconnects the unit when it sees the voltage go somewhere it should not. That is the usual solution and it is clean. Where a unit does not have it, or the installation calls for it, the alternative is a dedicated earth electrode for the charger, driven and tested instead of pushed in and forgotten about. We measure the electrode resistance and record it on the certificate.

Either way the work is certified under BS 7671 and, as a new circuit, notified under Part P. The same engineers who look after the rest of your electrics install the charger, so nobody is arguing later about whose circuit is whose when something needs looking at.

Workplace and fleet charging for Lincolnshire businesses

Workplace installations are a distribution problem more than a charger problem. Several bays sharing one supply need either a sub main sized for the full diversified load or dynamic load management across the group, and on plenty of sites both. For Micron Clean Ltd at their Swindon facility we installed a dual 22kW commercial charger fed from a dedicated sub main off the building's mains intake, with excavation, ducting, cable protection and all the surfaces made good afterwards.

Groundworks are usually the bigger cost and the part that disrupts a working site, so they get planned around your operation. Where a business already has solar on the roof, charging fleet vehicles in the middle of the day off your own generation is worth considerably more than exporting the same units. That is a conversation worth having before anyone decides where the bays are going to sit.