Updated on 14/02/25 by Ben_OVO
Three-phase meters
Three-phase meters are used when a home's electricity use has increased significantly. This could be because you've had an extension, or you're running large appliances like solar panels or heat pumps. Likewise, if your electricity demand has decreased, you might need to change to a single-phase meter. You’ll find out in this article how to change your meter to meet the demands of your property.
How to tell if you have a three phase meter
The best way to tell if a property has a three-phase supply is by looking at the electrical fuse (sometimes called electricity supply, service head, or cut out). Typically a single-phase will have one fuse and a three-phase will have three 100 amp fuses.
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Requesting an upgrade to a three-phase supply
- If you’re increasing the electricity demand required in your home (eg by installing multiple EV chargers or a new electric heating system) an electrician can advise whether you might need to upgrade to a three-phase supply.
- You’ll then need to contact your Distribution Network Operator (DNO), who’ll be able to upgrade your existing fuse to three-phase.
- You can then book with us to have your meter upgraded to three-phase. It’s usually about a month until an engineer can get to you. Check out our full guide to 3 phase meter maintenance costs here.
Can OVO install three-phase smart meters?
As part of the three-phase upgrade, it’s likely that a three-phase smart meter will be installed, but we can’t guarantee it.
For three-phase supplies we can sometimes install an ‘SMETS2’ smart meter. If you already have a three-phase supply, we can book an exchange for you, making sure that the job is sent to a three-phase trained engineer.
The process for downgrading your supply to single-phase
- You’ll need an electrician to check that your existing meter can be downgraded from three-phase to single-phase. You may also need an electrician to change some wiring to your electrical units.
- Again, you’d need your DNO to replace your fuse to a single-phase fuse or downgrading the fuse carrier.
- We’ll then arrange to have the meter exchanged in a separate appointment. Our lead times tend to be about a month. As this work would also require a three-phase trained engineer, it’s booked at the same cost and with the same time frame as an upgrade. A downgrade of your supply would also mean you’d be able to get a SMETS 2 meter installed.
If you know you need a three-phase meter, or want to downgrade a three-phase meter to a single-phase meter, please get in touch with our Support Team. Once the appointment is booked we’ll contact you if anything changes, or if we need to reschedule.
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Thanks,
The OVO Team