ECONOMY 7.... Anyone understand it ???

Brian99_2

Questions about "Economy 7", which guarantees 7 hours of cheap juice at night for storage heaters...

The switching on has to be staggered... but do they switch one house at a time ? By computer programs ? And are the commands sent by RADIO, or along the mains cables?

Also, can it be arranged for the whole house to go on cheap juice at night ?

HappyMJ

It's fairly random due to inaccuracies in everyones clocks in the meter box.

The whole house does switch to Economy 7 at night it's just an extra circuit that is activated for the heating to come on.

Brian99_2

It has all changed, and recent installations are digital, and I know they now send digital commands, so they have better control of the gradual switching on, for levelling out of the demand curve.

(Older systems may still be switching using timers).

We really need a guy from the trade.

grahamc2003

Brian99 wrote: »

Questions about "Economy 7", which guarantees 7 hours of cheap juice at night for storage heaters...

The switching on has to be staggered... but do they switch one house at a time ? By computer programs ? And are the commands sent by RADIO, or along the mains cables?

Also, can it be arranged for the whole house to go on cheap juice at night ?

All modern e7 meters are switched by radio - a signal on the analogue radio 4 frequency (at least mine is. I expect ones newer than mine probably switch via a digital radio frequency - sort of begs the question of what happens when the analogue signal is turned off in the near future).

Meters in the same area will all switch at the same time - so a big step in demand when e7 switches to cheap rate (and a much lesser step on switching to day rate). I expect the precise timing will be used such that the average frequency over the day is brought to 50Hz.

Correct e7 wiring means all use switches to cheap rate, but I think there are some people with old 'white meter' or other old off peak tariffs now on e7 where the wiring is such that only the heating switches to cheap rate, with other circuits still on the full rate.

mattcanary

Not all meters switch to the cheap rate via radio signal. Some switch through a timeswitch to which the meter is connected. The period in which the 7 hours worth of cheap electricity is calculated varies from property to property.

There is no rhyme or reason as to which 7 hours worth of cheap electric you get. It may be 12am - 7am, 12.30am-7.30am, etc. In addition, if your system is operated via a timeswitch, then the 7 hours do not chnage in line with the clocks changing for GMT / British Summertime

spiro

grahamc2003 wrote: »

All modern e7 meters are switched by radio - a signal on the analogue radio 4 frequency (at least mine is.

Incorrrect, most modern meters have an internal clock that does the switching. The ones that are tele-switched rather than time-switched are things like 'Winter Warmer' were the times depend on the weather. When Smart is rolled out it is possible that tele-switching (via radio broadcast) will cease as they will be able to remotely message the meter.

Brian99_2

Spiro - thats interesting.

My sister's meter is digital (2 years old); but the time of switching varies a LOT (ON at 10.30 pm, next night ON at 12 pm etc)

So if the timing varies like that, it cannot be an internal timer; it must be remotely switched yes ?

Cardew

Brian99 wrote: »

Questions about "Economy 7", which guarantees 7 hours of cheap juice at night for storage heaters...

The switching on has to be staggered... but do they switch one house at a time ? By computer programs ? And are the commands sent by RADIO, or along the mains cables?

Also, can it be arranged for the whole house to go on cheap juice at night ?

I see you live in Scotland.

In England for perhaps 30 years or so it has been normal practice for all electrical circuits to be switched at the same time - so, obviously, all electrical consumption would be at cheap rate for the 7 hours. There are some exceptions to the above.

In Scotland it was very common to have a variety of off-peak tariffs fitted to properties - not just E7 but varieties of E10 etc. - preumably because mains gas was not so readily available?

Many(most?) of these houses were wired initially so only heating/immersion heater switched over to cheap rate and the rest of the property remained on a single daytime tariff.

I have little doubt that all of the major companies will have no difficulty in allowing your property to be on the 'English' version of E7 but it will obviously require some modification of your house electrics.

grahamc2003

spiro wrote: »

Incorrrect, most modern meters have an internal clock that does the switching. The ones that are tele-switched rather than time-switched are things like 'Winter Warmer' were the times depend on the weather. .

Are you certain of that? Seeboard - the only area for which I can speak with confidence - started rolling out rts meters for e7 about 20 years ago, to replace the mechanically switched ones and their obvious drawbacks. I find it incredible that sometime in the last several years they reverted back to internally switched meters rather than rts. Why would they do that?

How does the varying times of e7 work with internal clocks? Sometimes, our cheap rate starts at 00:00 till 00:15, then 00:30 to 07:30 (with probably a 15 min of peak rate somewhere in there). Sometimes it simply starts at 12:30. As I said before, the rts allows a degree of frequency control for the grid which has requirements to average the frequency very close to 50hz at the end of each day - mechanical timers take away that facility.

Do you have any referneces for the actual meters installed for e7 under the meter replacement obligation?

Edit - Just reread your post again and it looks like you are saying that no e7 meters are teleswitched. If that is what you are saying then you are definitely incorrect.

Brian99_2

This discussion is producing a good range of answers, and no doubt the truth will gradually emerge !

My sister's house is in quiet English Lakeland with no gas, the E7 timing DEFINITELY changes day to day. Neighbour finds the same. We believe it is teleswitching. But WHO sends the signals ? We need to know why the AGA is clocking up some full-rate units at night as well as cheap-rate units. WE always beleived it was purely using solely cheap units at night.

If the modern meters have complex internal software, which can choose intelligently the best times to switch E7 on and off, (depending on voltage or frequency) maybe someone can confirm this ??? Otherwise I'll assume they dont

Richie-from-the-Boro

As far as I'm aware Scotland still doesn't call it E7 they still call it by the old name White Meter, though that may have changed since Scottish Power became a big player in the very small E7 arena. The O/P may be in Scotland but is his sister also in that area ?

I've no idea how many of the old 'timeswitch' systems still remain while I'm sure there are some in the scheme of things it must by no be minuscule compared to the total UK-E7 households.

Similarly the Radio time switch was originally done by Region, I don't know of any single Region that isn't now on timeswitch. I do however agree that there are variations of ON/OFF between both suppliers & Regions that are give or take within 30 minutes of each other.

Brian99's sisters 90 minute variation doesn't fit anything I can think of