A 7kW EV charger draws 32A at full whack. If your incoming main fuse is 60A, you have a problem the day you run the shower while charging. If it is 80A you are fine most of the time. If it is 100A you can charge and use the house without thinking about it. Every rural install starts with checking which one you have.
What is my incoming main fuse?
Look at the meter cupboard. The DNO cut-out is the sealed unit that the meter tails come out of. There will be a label on it (or a stamp on the fuse carrier) saying 60A, 80A or 100A. Older rural properties are often 60A. If there is no visible rating, we test at the survey visit.
Load management (CT clamp)
All modern smart chargers - Ohme, Zappi, Wallbox, Hypervolt - accept a CT clamp on the incoming main. The charger reads real-time house load and throttles down when the shower or oven is on, then throttles back up when they finish. On a 60A supply this is the difference between a legal, safe install and a nuisance-tripping mess.
When you need a supply upgrade
- Two EVs and both charging at 7kW at the same time.
- 7kW charger plus air-source heat pump plus induction hob all on peak.
- 22kW three-phase charger request (needs a three-phase supply - most Wingham rural properties are single-phase).
Any of these and we apply to UKPN Southern for a supply upgrade. A single-phase 100A upgrade is usually free but takes four to six weeks. A three-phase change is chargeable and can take longer.
G98 vs G99
G98 is the fast-track DNO notification for small installations under 16A per phase - a standard 7kW charger with load management falls here. G99 is the slower pre-approval route for anything larger, or for chargers without load management. Every charger we install includes the DNO paperwork filed on your behalf.
Cable routing on farmhouse plots
Direct-buried SWA in a trench where the run is over 15m, with a warning tape 150mm above and a proper draw pit if there is a bend. Surface clipped in white PVC conduit only where the route is short and along a garage wall. Bright orange trench markers on any drive crossing. We agree the route with you before quoting so nothing changes on the day.
Solar-diverter setups
If you have solar PV, a Zappi can divert surplus into the car instead of exporting at 15p and re-importing at 30p later. Payback improves by another year or two on top of the standard charger. Worth specifying at install time even if you plan to add PV later.