combining economy 7 and 24hr supply

[phantom1129]

Hi guys
customer has an electric AGA currently supplied on radial from consumer unit with single supply.
he intends to get economy 7 and wishes to run the cooker on this supply when available.
i cannot run an additional cable.
i am looking for an automatic relay switch (or similar) which would sense the economy 7 supply and automatically switch over and then back again as soon as this supply disappears.
what would you suggest

 

[Rockingit]

Search the forum as there was a thread on this subject a little why ago and someone had a really good idea that I now can't remember!

If not, you could use a NC/NO contactor and have the E7 as the coil circuit, E7 as the N/O and daytime supply as N/C, wired back at the board into a Y onto the one cable. You'd need it to be a hefty one though just in case it had to switch just as the AGO was using heat - no idea what the surge/arc might be on that!

 

[snowhead]

Are they going to be cooking overnight?

If they are having E7 fitted now, it will be dual rate meter so everything is automatically E7 in the relevant hours.

Older E7 had 2 meters and a timeswitch and contactor for E7.

 

[Rockingit]

Are they going to be cooking overnight?

If they are having E7 fitted now, it will be dual rate meter so everything is automatically E7 in the relevant hours.

Older E7 had 2 meters and a timeswitch and contactor for E7.

It was the older style I was thinking of.....distinct sense of deja vu here!!