What are mu e7 times??

That makes sense, the small white meter is feeding the smaller CU via a timeswitch, so the heating kicks in and out at certain times of day. I can't read what it says on the MCB labels, but it would be logical for all the other circuits in the house (sockets, lights, cooker etc) to be run off the other CU which isn't controlled by the timeswitch and is fed from the larger meter with the transparent case.

I don't know for sure, but I've never seen an Economy7 set-up like this - usually all an Economy7 timeswitch does is switch the recording of consumption between one meter register and another. So all your consumption (lights, heating, power etc) at night will be charged as Economy7 night units.

However, there were many different tariffs for storage heating etc which operated using separate meters and circuits like the ones in your pictures - so are you sure you are on Economy7? Do the day and night unit charges you are paying correspond to the published E7 tariff for your supplier?

If you are definitely on E7 and your night units are being recorded on the white meter, and as per molerat's post you are also getting cheap rate heating between 1400-1700, then it looks like you are probably getting a very good deal , even if your non-heating consumption is all being charged at the day rate.

m0bov, you should still check your bills/contract to ensure you are on the right tariff, and also that the readings on the bills correspond with the meters on the wall - i.e. that the cheaper rate electric is being charged for the heating.

From what I understand, the Economy 10 tariff didn't come into being until the 2000's, one source says 2004. The timeswitch you have is much older, perhaps 1960's, and certainly was in use in 1990. So it is quite possible your arrangement of meters and CU's predates the introduction of Economy 10 and therefore the tariff you are actually on could be one of many, not all of which are good value for money.

What you need to find out and assure yourself is whether you are still being charged on some kind of legacy tariff, or Economy 10, or Economy 7.

I'd have thought that E7 would only have one meter with a day and night rate. You've got two meters, how are they being billed/recorded.

E7 implies that all your leccy during the night would be at off-peak rates and full price during peak times. As you've got two meters it looks like one is configured to supply the heating and hot water via a timed supply and the rest via a non timed supply (unless the main meter is a dual rate)

Check your bills to see what tariff you are actually on