Off Peak Tariff

sebtomato

Scrounger said:

@Sebtomato I wish you were right. 

Sadly, the smart meter billing schedule and the ALCS (E7 100A Contactor) schedule can be different.  

Sorry, I still don't see how the contactor can be on a different schedule from the meter.

Unless the contactor is still powered by a box receiving a radio signal, rather than directed connected and controlled by the smart meter.

In my case, I am on E7, I have a 5 pole smart meter (one pole being used to control an external contactor), and R1/R2 rates and contactor are changing exactly at the same time.

MWT

sebtomato said:

Scrounger said:

@Sebtomato I wish you were right. 

Sadly, the smart meter billing schedule and the ALCS (E7 100A Contactor) schedule can be different.  

Sorry, I still don't see how the contactor can be on a different schedule from the meter.

The 'how' part is easy, 'why' would be less clear...

The smart meter has a schedule for switching between the 4 available registers and a schedule for the ALCS operation.

For E7 those two schedules should be the same so it switches between R01 & R02 and switches the ALCS at the same time.

If the schedules are not the same then you have a problem obviously.

It is more understandable how the problems can occur when dealing with half-hour based tariffs as they do not need to use R02 but do still need to switch the ALCS on/off at the right time.

Regarding the Bright app, it must be remembered that it is always going to reflect tariff information that is currently loaded onto the meter, it is not using data from elsewhere or using the same data as the billing system at your supplier (with the exception of the Agile tariff), so if the meter data is not up to date then anything it tells you about cost can be wrong.

Phones4Chris

sebtomato said:

Phones4Chris said:

The information you can see there doesn't represent what you'll see on your bill. What the Bright App shows - which is usually the same as what the IHD shows - is the generic off-peak times for your area which are what you are seeing, which is what is being displayed on the Time of use rates chart. The actual switching time can vary from user to user (so there isn't a huge surge in the load).

I agree that the time to switch to off peak/peak time is different between individual meters. Some small variations are introduced to avoid power surges (lots of meters moving to off-peak at the same time). However, it should be by a few minutes maximum, not 30 minutes.

In my case, off peak currently finishes at 08:35 as opposed to 08:30 for instance. That's for both the IHD (rate displayed is changing at 08:35) and the contactor (off peak circuit is no longer powered), powered directly by the smart meter (5 poles).

However, I disagree that the Bright App shows some generic data in the area. I believe it shows data sent by your own meter, and rates applicable for each 30 minute period.

I believe the rate is what applies at the end of the 30 minute period.
For instance, period starts at 08:30. At 08:59, consumption for that period was x kWh and rate applicable at 08:59 was x pence.

When I download my 30 minutes data from the Bright API, the rate applied for the 08:30 time period is peak rather than off peak (or some average), which is mainly correct for the bulk of the period, but slightly over estimated.

@sebtomato - My reply was to @Scrounger, but in the main could equally apply to you, but as I haven't seen any post from you saying what your off-peak times are, some remarks may not be applicable.
Who said the actual switching was 30 minutes from the generic time for the area? I have seen it quoted that it is normally +/- 15 minutes BUT the actual times are down to the supplier according to my DNO, and you've just stated yours turns off at 0835 instead of 0830 so I don't know why you are bringing 30 minutes into this with reference to your own situation.

(I have now seen another thread about your supposed off-peak times, but I'm not going to comment on that here).
It seems to me that both you and @Scrounger seem to think that what you are seeing on the Bright App is what you are/will be billed - not so. As I've already said you need to go and watch your meter and see exactly what times it switches between the peak and off-peak registers and whether the ALCS switches at the same time - and then look at you BILL!
From what you've said here, you IHD is consistent with your meter, mine isn't and it doesn't seem that @Scrounger 's is either, and the Bright App isn't for the 3 of us. As already mentioned, why this disparity is yet to be discovered.
Also

MWT said:

sebtomato said:

Scrounger said:

@Sebtomato I wish you were right. 

Sadly, the smart meter billing schedule and the ALCS (E7 100A Contactor) schedule can be different.  

Sorry, I still don't see how the contactor can be on a different schedule from the meter.

The 'how' part is easy, 'why' would be less clear...

The smart meter has a schedule for switching between the 4 available registers and a schedule for the ALCS operation.

For E7 those two schedules should be the same so it switches between R01 & R02 and switches the ALCS at the same time.

If the schedules are not the same then you have a problem obviously.

It is more understandable how the problems can occur when dealing with half-hour based tariffs as they do not need to use R02 but do still need to switch the ALCS on/off at the right time.

Regarding the Bright app, it must be remembered that it is always going to reflect tariff information that is currently loaded onto the meter, it is not using data from elsewhere or using the same data as the billing system at your supplier (with the exception of the Agile tariff), so if the meter data is not up to date then anything it tells you about cost can be wrong.

If the meter data is not up to date, then anything it tells you about cost WILL be wrong!

Phones4Chris

sebtomato said:

Scrounger said:

@Sebtomato I wish you were right. 

Sadly, the smart meter billing schedule and the ALCS (E7 100A Contactor) schedule can be different.  

Sorry, I still don't see how the contactor can be on a different schedule from the meter.

Unless the contactor is still powered by a box receiving a radio signal, rather than directed connected and controlled by the smart meter.

In my case, I am on E7, I have a 5 pole smart meter (one pole being used to control an external contactor), and R1/R2 rates and contactor are changing exactly at the same time.

IF that were to be the case with a Smart meter installed, then it would have to be a completely bodged smart meter install because he said he has a 5 terminal smart meter!!

Scrounger

Thank you everybody for your thoughts, and in particular @MWT & @Phones4Chris for your helpful info.

I'm now at the flat and have done some checks his morning during switching time at the meter.

The setup is here similar to my main HQ: Aclara SGM1416-B 5-port meter wired to two fuse boards (peak & off-peak).(Incidentally, at Scrounger HQ, all the timings seem to be correctly syncronised: billing, ALCS, IHD & Bright - though I now need check at the meter in light of the info from Phones4Chris and what I saw happen at the flat today).

The flat has 6 storage heaters on the off-peak board on individual mcbs feeding from terminal 5 of the meter. The IHD here is a Chameleon IHD3.

This is what happened at the meter (load approx 6kW):

Time BST  IHD display    Meter active register   ALCS 

07:55         off-peak               R02                      on

08:00         peak                    R02                      on

08:05         peak                    R02                      on

<08:09*     peak                    R01                      on

08:36         peak                    R01                      off

R02 = off-peak

R01 = peak

* approximate time of meter changeover R02 to R01 

Conclusion

1. @Phones4Chris is correct in that the IHD does not tally exactly with the meter switchover times.

2. Notwithstanding the above, my ALCS is active for 27 minutes at peak rate (per day) resulting in overcharging.

I'm here all week, do I need to take any further measurements for clarification?

Happy Easter Monday btw.

Scrounger

Phones4Chris

Scrounger said:

Thank you everybody for your thoughts, and in particular @MWT & @Phones4Chris for your helpful info.

I'm now at the flat and have done some checks his morning during switching time at the meter.

The setup is here similar to my main HQ: Aclara SGM1416-B 5-port meter wired to two fuse boards (peak & off-peak).(Incidentally, at Scrounger HQ, all the timings seem to be correctly syncronised: billing, ALCS, IHD & Bright - though I now need check at the meter in light of the info from Phones4Chris and what I saw happen at the flat today).

The flat has 6 storage heaters on the off-peak board on individual mcbs feeding from terminal 5 of the meter. The IHD here is a Chameleon IHD3.

This is what happened at the meter (load approx 6kW):

Time BST  IHD display    Meter active register   ALCS 

07:55         off-peak               R02                      on

08:00         peak                    R02                      on

08:05         peak                    R02                      on

<08:09*     peak                    R01                      on

08:36         peak                    R01                      off

R02 = off-peak

R01 = peak

* approximate time of meter changeover R02 to R01 

Conclusion

1. @Phones4Chris is correct in that the IHD does not tally exactly with the meter switchover times.

2. Notwithstanding the above, my ALCS is active for 36 minutes at peak rate (per day) resulting in overcharging.

I'm here all week, do I need to take any further measurements for clarification?

Happy Easter Monday btw.

Scrounger

Oh dear, it looks as though there's an EDF !!!!!!-up here, but it's not 36 minutes, it's 36-9=27 when R01 becomes active in the morning.
I would check exactly what happens tonight when the E7 off-peak should/does start and the same in the morning when it does/should end BUT have your camera handy to take some photos (practice beforehand!).
You should be able to see on the meter display in the bottom RH corner some little switch symbols, make sure they are nice and clear in your photos.

I think I would have the TOU Rate 2 displaying when it changes to R02, and also when the ALCS operates.
I'd have TOU Rate 1 displaying in the morning when it changes to R01 with the ALCS still active and also when it turns off.
(I think I've got those the right way round!). Do remember though that when you select what you want to display (Rate 1/2 etc) the meter will switch the display to the next one in the order by itself, I've never needed to time how quickly it does it, so check yourself so you can be sure you'll have the right one displaying when you take the photos.

One (minor?) problem is that with the milder weather atm, there may be no demand from the storage heaters tomorrow at switch over time unless you can be certain of getting something on your storage heater to be operating over those 29 minutes so you can take a sequence of photos from 0805, 0809 to 0836 showing the kWh increasing - a little bit of maths suggests make sure it's a 3.4kW load to be certain the units will go up between start and end. Also make sure there's no significant other domestic equipment operating during this time that would clock up consumption - eg. kettle, toaster, cooker etc etc. so at least you can say everything else was switched off - BUT if the two consumer units are close enough to the meter, and it's of no consequence to turn off the domestic consumer unit (eg. be wary of alarm systems etc) take extra photos during those 29 minutes showing it switched off, then they can't argue!

I presume, in normal circumstances (when you aren't there) your normal daytime (Rate1) consumption is very low, possibly consistent from day to day? Look at all the evidence you have from previous billing (possibly only Scottish Power - depends on when the anomaly with the ALCS timing started. When you switched to EDF, do you know how quickly the meter/IHD came up with the Welcome to EDF message? That's when the meter data will have been updated, incorrectly by the looks of things). You will no doubt need this when arguing the toss with EDF about your Rate 1 billing. It's unlikely you can predict what the Rate 2 consumption might have been because it's likely there'll be no demand in the latter part of the night from the storage heaters in the milder weather.

I don't know if your meter has been updated with the correct tariff rates (check against you TIL), if not, take some separate photos of the meter displaying the wrong rates - Rate 1 in daytime, Rate 2 in offpeak - they each only display in those time periods, the daily charge as well, but that will show all the time.

Hope that helps, If I think of anything else, I'll post again.

Phones4Chris

Just to say I've edited my post to add a bit about turning off the domestic consumer unit in the morning if possible, in case you've read my post before I edited.

Scrounger

Thank you @Phones4Chris for all your advice.

Of course you are right, 27 minutes overcharge per day (approx £75 per year by my rough estimates).

My initial estimate prior to the site visit was 30-minutes overcharge which was only 3-minutes out (and this was using only the Bright app data and graphs).  EDF have recently added some graphical tools in their online account but is next to useless - certainly no 30-minute breakdown available.

EDF have been in touch and say that they are hoping to amend my meter timings remotely.  So they do seem to be listening.  Once this has been done I'll then review the timings myself and report back here.

I just wonder how many more customers are similarly affected and being overcharged every day without knowing it; could be hundreds or thousands. 

Scrounger

Swipe

Scrounger said:

I just wonder how many more customers are similarly affected and being overcharged every day without knowing it; could be hundreds or thousands. 

Scrounger

Almost certainly. I stayed up on the day my smart meter was installed to find out the exact time it would switch over and made sure the rate 2 register was in use at the time.

Scrounger

Scrounger said:

The chart above shows at 08:00 the billing changes from off-peak (£0.14) to peak rate (£0.29) but the ACLS contactor is not switching off until 08:30
Hence the spike in cost for the final 30 minutes (right chart).

Update: 02 May 22:

Interestingly, I re-visited the Bright data for 14 April 22 yesterday and noticed the cost chart has now changed (for the worse) - the peak rate is now shown starting an hour earlier than before (right chart, sorry about the change in y-scale).

AKAIK there has been no intervention by EDF as yet (the latest is that they are now insisting on a site visit!).  The Bright time of use and rates remain unchanged.

Any ideas why the Bright cost chart has changed (the kWh chart is unchanged)?

Scrounger