Meters and In-Home Displays (IHD)Smart meters

Smart relay device: what it is and how it works

A smart relay device passes the signal from one smart meter to the other if they’re too far apart. Find out everything you need to know about smart relays.

Here’s our handy guide to smart relays. Find out what smart relays are, how they work and how to solve problems. 

What's a smart relay device?

A smart relay does exactly what you’d expect. It ‘relays’ the signal from one smart meter to the other, if they’re too far apart. Or between smart products, like your In-Home Display (IHD) and your smart meters.

First we need to find a good location for the smart relay. Once we’ve got one, it could extend the Home Area Network (HAN) in your home by 100 metres. That’s unless there are any annoying thick walls in the way. 

What is HAN?

HAN stands for Home Area Network. It’s a secure wireless system in your home that links up your smart products and smart meters. It’s a completely separate network to your Wi-Fi.

Why do the meters need to communicate with each other?

Your smart electricity meter uses the HAN to communicate with your smart gas meter and pick up its readings. Your gas meter can’t give us gas readings on its own, or send information to your IHD or smart equipment.

How much does it cost to run a smart relay?

If you leave it on non-stop for 365 days, a smart relay will use 8.76 kWh of power. That would cost you around £1 a year. 

Your smart relay doesn’t need to be on every day (and we know it’s not always possible). But if it is, there’s more chance of your meter readings reaching us in time for your billing date. Also, if you’ve opted for readings ‘every half hour’, you’ll find the insights about your energy usage more detailed and useful.

How to get a smart relay device

You’ll get one free if we find that your smart electricity meter isn’t communicating well with your smart gas meter. Normally, we’d find out because you’d tell us you’re having problems

If we’ve decided to send you a smart relay, it can take up to 3 weeks to arrive at your door.

What if I need more than one smart relay?

No problem – if you’re an OVO Energy smart customer they’re all free. You can have up to 4 smart relays working together to cover the HAN range, if your home is really big.

How to install a smart relay device

  1. Plug it into a power socket – but don’t switch it on yet. The socket should be close to halfway between the gas and electricity smart meters, so it can pair them properly. If the socket is in use for another appliance, use the socket on the smart relay for the appliance instead.

  2. Next, you’ll need to call us before turning the smart relay on.

  3. We’ll remotely put your electricity smart meter into ‘search’ mode, so it searches for your smart relay.

  4. You can then switch the socket on. A red light will come on just beneath the long black button at the top of the smart relay.

  5. Hold down the black button for around 15 seconds. The red light should start flashing.

  6. The red light will then stop flashing and turn off. That means the smart relay’s now linked to your HAN. So, your gas and electricity meters should now be able to communicate with each other. All done!

What do the lights on the smart relay mean?

  • Solid red light: the smart relay is in standby mode. It isn’t connected to a HAN at the moment, and it’s not searching for one to link with.

  • Flashing red light: the smart relay is in search mode. It’s searching for an open HAN to join.

  • No light: the Smart Relay is now “commissioned”. That means it’s joined the HAN and is now communicating with your electricity meter.

What happens if I turn the smart relay off?

Any devices outside the electricity meter’s range will stop talking to it. For example, if you have an IHD, it will stop giving you real-time information. That’ll be the case until you move it within range of the electricity meter, or switch the smart relay back on.

If you're having any problem with your smart relay device, bear in mind that turning it off won't reset it.

I plugged in my smart relay, but the red light didn't come on. What should I do?

If you’re plugging in your smart relay for the first time and the red light doesn’t light up when you switch it on, try plugging it into a different socket. If the red light still doesn’t come on, get in touch with us through our online chat

My smart relay stopped working: what should I do?

If it’s stopped working because you’ve recently moved it, try moving it closer to the electricity meter. If that doesn’t work, get in touch at [email protected] 

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