Economy 7 - historic wiring

[Mark56]

I rent out a 1989 era flat, all-electric. I am having trouble understanding what is going on with the wiring to the immersion heaters and what used to be a storage heater but is now a panel heater.

The hot tank has two immersion heaters, each with its own switch.

The meter supplying the flat is modern and has a digital display that shows two readings i.e. day and night. It has 2 x L coming out of it.

Am I right to think that back in the day there were two separate supplies, one for day and one for night? Perhaps with two meters, one for day and one for night, so that consumers could be billed for each?

However, now, with chips in the meters, the meter knows when it is day/OP and can store each reading without recourse to separate circuitry in the flat?

Doesn't it mean that any draw on any circuit will be rated low tariff if it is OP and at a higher rate when not OP?

Would there be two live cables coming from the meter because the two used to be required in the past but that they are not required now?

So, can I have the OP circuits removed and just have everything run from the CU without worry about losing the lower tariff?

 

[Murdoch]

If you have a dual tariff it will be costing you money.

As for the circuits, how many fuseboards do you have?

 

[Mark56]

There is one fuseboard/consumer unit.

However, my main question is about the historic wiring.

Is the old separate wiring of night/day appliances now redundant due to the arrival of meters that record both night/day usage?


Yes, I am beginning to appreciate that the dual tariff is a way to lose money. At 39p per day unit you have to use a lot of night units at 14p to make it pay.

 

[Murdoch]

There is one fuseboard/consumer unit.

Is the old separate wiring of night/day appliances now redundant due to the arrival of meters that record both night/day usage?

without looking in person it’s almost impossible to confirm either way.

do you have an immersion heater off the E7 ?

sorry if this isn’t helpful

 

[ProDave]

Who convinced you it was a good idea to remove the storage heaters, that would have cost 14p per unit to heat up, with panel heaters that don't store heat so need to be used on the day rate of 39p?

In other words who convinced you the new heating system that will cost you double or more to use, was a good idea and in just what way will you benefit from it?

IF you are going to replace storage heaters with panel heaters, at least switch to a single rate tariff that would probably be about 28p at the moment, which is still better than 39p.

 

[Gian]

There is one fuseboard/consumer unit.

However, my main question is about the historic wiring.

Is the old separate wiring of night/day appliances now redundant due to the arrival of meters that record both night/day usage?


Yes, I am beginning to appreciate that the dual tariff is a way to lose money. At 39p per day unit you have to use a lot of night units at 14p to make it pay.

You have to manage your use. We use timers on our appliances many have delayed timers built in. We do this to maximise our saving buy using as much of the economy 7 rates. So washing machine ,dishwasher , ev charging, sauna are all going on in the e7 times. We even have chest freezer on timers to switch off at midnight and come back on at 6 am this is also for our American fridge freezer. We go as far to even make bread ready for morning and cook using pressure cookers during these times. In the summer it's not so bad as we have 10kw solar so ev would charge just using solar and timers would switch to day as long as we know weather is good. It's about what you want out of it. For me I don't want to pay for electric lol.

 

[stuboy]

I remember puzzling over E7 the first time i saw it, but then it dawned on me that i am thick, here's how it works:-

Henley blocks on your meter tails split the feed:- One goes to your main DB the other goes via a time switch (100A contactor) to the E7 DB, ie heaters etc.
When your meter gets the E7 signal it engages the contactor and switches registers to start recording on your E7 tariff. ALL your electricity used will get charged at the night rate until it switches back off again. In the summer (I'm Western Power) its 1am till 8am for mine!
Hope that helps.
Stuart

 

[Mark56]

Thank you for your replies.

Is it like this?

Originally, when E7 was introduced, the time switch was in the meter (as per stuboy).

The meter fed power to two consumer units/DBs:

1. An E7 CU. This fed power to the storage heaters and immersion heaters. There was no need for timer switches on the appliances as they would be switched on by the meter at the right time.
2. A general purpose CU that fed power everywhere else.

During E7 time, all power use, via either CU, would be charged at the E7 rate. So, heaters automatically switched on but lights and kettles still work on E7 rate.

Now things have changed as meters are electronic and there is no need to have two CUs connected to the meter as it is easy enough to add time switches to the appliances. With appliances on timers, the E7 can be used to heat water or storage heaters without the need for a separate CU.

(I see the point that without storage heaters it is hard to justify E7, which is probably why it is being phased out.)

 

[Gian]

Thank you for your replies.

Is it like this?

Originally, when E7 was introduced, the time switch was in the meter (as per stuboy).

The meter fed power to two consumer units/DBs:

1. An E7 CU. This fed power to the storage heaters and immersion heaters. There was no need for timer switches on the appliances as they would be switched on by the meter at the right time.
2. A general purpose CU that fed power everywhere else.

During E7 time, all power use, via either CU, would be charged at the E7 rate. So, heaters automatically switched on but lights and kettles still work on E7 rate.

Now things have changed as meters are electronic and there is no need to have two CUs connected to the meter as it is easy enough to add time switches to the appliances. With appliances on timers, the E7 can be used to heat water or storage heaters without the need for a separate CU.

(I see the point that without storage heaters it is hard to justify E7, which is probably why it is being phased out.)

With the prices now I think it's a huge mistake to phase out e7. It saves me loads each year.

 

[michael8554]

With my Economy 10 fed house, everything - rings, lighting, storage heaters etc - is powered via a big "clockwork" timeswitch-cum-contactor.

It's set to GMT, so the switches occur 1 hour later in the summer.

 

[Mark56]

Who convinced you it was a good idea to remove the storage heaters, that would have cost 14p per unit to heat up, with panel heaters that don't store heat so need to be used on the day rate of 39p?

In other words who convinced you the new heating system that will cost you double or more to use, was a good idea and in just what way will you benefit from it?

IF you are going to replace storage heaters with panel heaters, at least switch to a single rate tariff that would probably be about 28p at the moment, which is still better than 39p.

The storage heater was u/s. But point taken.