The main fuse controls the amount of power coming into your home. You might need a main fuse upgrade if you’re having an EV charger installed, or if you’ve had work done at your property which means you’re going to use more energy. 

To arrange an upgrade for your electricity main fuse, contact your distribution network operator. Distribution network operators (DNOs) manage the distribution of electricity around the country. And they own and operate the wires that carry electricity from the grid into your home. You can use your postcode to look up the DNO for your area. Or, if you’re getting an EV charger installed, your installer will help you to contact them.

Your DNO will usually try to visit within 2 weeks of you contacting them. The upgrade is free of charge.

Before you contact the DNO, check your property is ready for a main fuse upgrade

If you’re having work done on your house, or an EV charger installed, your electrician or EV installer will help you check your existing meter set up. You might need to complete some additional work at your property before the DNO can upgrade your main fuse. For example, you may need to upgrade your electricity meter wires (known as ‘meter tails’) or install an isolator switch.

In some cases, your electrician or EV installer will be able to complete any work that needs to be done for you. Or they might recommend you contact us, at Bulb.

These are some things to check you have in place before you contact the DNO.

Check your fuse board and consumer wires are the right size

An electrician will be able to help with the consumer wires. Getting a new fuse board (or 'consumer unit') generally costs around £500.

Check your electricity meter wires (‘meter tails’) are the right size 

You may need new meter tails to handle the increased supply of electricity. You can contact us to arrange a meter tails upgrade. The cost of this work is £120. 

Check if you need to install an isolator switch

An isolator switch enables an electrician to isolate the flow of electricity to the mains if they're working on your property. Our meter engineers can fit an isolator switch for you. The cost of this work is £120. Find out more about getting an isolator switch installed.

Check what size fuse you need

Your DNO will ask what size fuse you need. You can usually check what amp your existing fuse is by looking at the fuse rating on the side. You can upgrade from a 30amp or 60amp fuse to either an 80amp or a 100amp fuse. The size of fuse you'll need will depend on why you’re upgrading it. Ask your electrician or EV installer for their recommendations.


Contact us at least 3 weeks in advance to upgrade your meter tails or fit an isolator switch

If you need an upgrade to your meter tails or to get an isolator switch installed, contact us to arrange an engineer appointment. Let us know if you’ve got a DNO visit planned, and we’ll arrange for an engineer to visit and complete the work before your DNO appointment. Engineer availability varies from area to area, so it’s best to contact us at least 3 weeks before you need the work done.



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