The cut-out is the sealed unit where the electricity supply enters your home, and the fuse inside it — commonly rated 60, 80 or 100 amps — caps the maximum your whole property can draw at once. A typical 7 kW home charger uses about 32 of those amps on its own, for hours at a time. So the fuse rating decides whether a charger fits comfortably alongside your other loads, or whether the supply needs attention first.
Key Takeaways
- The main cut-out fuse — commonly 60, 80 or 100 A — caps your whole home’s draw.
- A 7 kW charger takes about 32 A of that, for hours at a time.
- The cut-out is the DNO’s equipment: never open it or pull the fuse yourself.
- Small fuses are usually worked around with load management, scheduling, or a DNO upgrade.
Where the Cut-Out Sits, and What the Rating Means
Power arrives from the street into the cut-out, passes through the main fuse, then through your meter and into your consumer unit, which splits it into the circuits around your home. The cut-out and its fuse belong to your distribution network operator (DNO), not to you and not to your energy supplier. The rating is sometimes printed on the fuse carrier: it is the current at which the fuse operates to protect the supply cable. Older homes commonly have 60 A fuses; many newer or upgraded supplies have 80 A or 100 A. Your installer reads the rating, and your home’s likely maximum demand, as part of the survey covered in our wallbox installation guide.
| Main fuse rating | Whole-home ceiling (rating × 230 V, rounded) | What it usually means for a 7 kW charger |
|---|---|---|
| 60 A | About 13.8 kW for everything at once | The tightest common case: a charger plus an electric shower or cooker can crowd the limit, so load management or a reduced rate is likely |
| 80 A | About 18.4 kW | Usually workable, with sensible scheduling of the biggest loads |
| 100 A | About 23 kW | Comfortable headroom for a charger alongside normal household use |
Treat the middle column as a ceiling, not a target. Your installer’s maximum-demand assessment — which allows for the fact that not everything runs at once — is what actually decides; supply surprises are one of the factors that change installation cost.
Why You Must Not Touch the Cut-Out
The cut-out is sealed for a reason. The fuse protects the DNO’s cable, the terminals inside are live whenever the street supply is live, and the unit is network equipment. Never open it, never pull the fuse to “check” anything, and never let anyone but the DNO or its authorised contractor work on it. If the rating is unreadable, or the unit looks damaged or hot, phone the DNO — your installer can help, but cannot do the DNO’s part of the job.
What Happens If Your Fuse Is Too Small
A small fuse does not automatically rule out a charger. Installers usually work through these options in order:
- Load management. A charger or clamp that watches the home’s total draw and throttles charging when the house is busy, so the pair never crowds the fuse.
- A lower charging rate. A 7 kW-class load reduced at the charger leaves more room for everything else, at the cost of longer sessions.
- Scheduling. Charging overnight, when showers, ovens and tumble dryers are off, avoids the clash entirely.
- A fuse upgrade. The DNO replaces the fuse — and, if needed, the cut-out — with a higher rating, provided the supply cable itself can support it.
For scale, the load is an ordinary one: a portable unit such as the EVDANCE EV-ACS3210E draws about 7 kW on a single phase, like a typical wallbox session. Three-phase homes are a different conversation, around units like the EV-ACT3204PE (three-phase, Type 2, RFID and app control) — and one that starts with the supply, not the charger.
Frequently Asked Questions
Is a 60 amp fuse enough for an EV charger?
Often yes, with load management or a reduced charging rate — but it is the tightest of the common ratings. Your installer’s maximum-demand assessment gives the real answer for your home, not a general rule.
Who can upgrade my main fuse?
Only your DNO. Your installer or supplier can help you request it, but the cut-out and fuse are network equipment, booked with the network operator.
Can I check the fuse rating myself?
You can read the rating printed on the cut-out if it is visible, without opening or disturbing anything. If nothing is readable, leave it alone — your installer can confirm the rating with the DNO.
Related Reading
- What Is a Standard EV Charger Installation?
- What Affects EV Charger Installation Cost? 8 Factors to Check
- Wallbox Home Charger Installation Guide 2026
- How Long Does It Take to Charge an EV at 7 kW, 11 kW and 22 kW?
