Smart Meters

EachPenny

Rubidium wrote: »

I think that you can forget your Monty Python theory, as it is simply not how it works in reality.

Monty Python?

Just to clarify, do you have an IHD which displays actual register values, if so could you please share the make/model as there are a few people on here who would be interested to know.

Also, if that isn't how it works, do you know because you've read a technical specification and confirmed it? Again, if so, could you please share your source?

Many thanks.

Rubidium

EachPenny wrote: »

Monty Python?

Just to clarify, do you have an IHD which displays actual register values, if so could you please share the make/model as there are a few people on here who would be interested to know.

Also, if that isn't how it works, do you know because you've read a technical specification and confirmed it? Again, if so, could you please share your source?

Many thanks.

Monty Python?

Yes see here

I do not have smart meters and will refuse them until the current sorry state of affairs has stabilised and SMETS2 meters are fully functional with the DCC, whenever that may be.

I am not aware of any IHD that display gas usage in M3 but this is obviously available on the gas meters screen, where a button needs to be pressed to preserve the gas meters internal battery life.

There is plenty technical information published and has been for years, including the additional features added by the SMETS2 specification e.g. start here

You know that smart meters can be used as prepayment meters as well as credit meters. When used for prepayment the IHD can be used to apply top-ups and therefore the HAN has to be bidirectional. Messages can be displayed on the IHD e.g informing you about changes to your tariff from a certain date.

I have already shown you that the IHD displays the calorific value and the conversion factor used to calculate the chargeable kWh from the cubic metres registered on the actual gas meter.

The information is out there is you really want to learn but please leave the theories to Monty Python, as guessing helps nobody.

victor2

EachPenny wrote: »

Just to clarify, do you have an IHD which displays actual register values, if so could you please share the make/model as there are a few people on here who would be interested to know.

I look after an account for somebody who has smart meters fitted by EON and even though she is no longer with EON, she can still read her meters from the in-house display EON provided.
Other suppliers publish the details of how to read your meters from the IHDs. Here's two:
https://www.edfenergy.com/for-home/energy-efficiency/smart-meters/home-energy-monitor-detail
https://www.scottishpower.co.uk/pdf/smart-meters/Smart-energy-display-user-guide.pdf

EachPenny

Rubidium wrote: »

I am not aware of any IHD that display gas usage in M3 but this is obviously available on the gas meters screen, where a button needs to be pressed to preserve the gas meters internal battery life.

...When used for prepayment the IHD can be used to apply top-ups and therefore the HAN has to be bidirectional.

The information is out there is you really want to learn but please leave the theories to Monty Python, as guessing helps nobody if presented as undisputed fact.

Funny sketch, but not sure of the relevance to smart meters?

victor2 has helpfully identified at least two examples of IHD's showing actual gas meter readings in M3, so we all learn something new every day.

The HAN may be bidirectional, some IHD's may be capable of bidirectional communication via the HAN, but that doesn't necessarily mean all IHD's have that capability - a point I made when first raising the possibility of the communications link being a factor.

I've made a little amendment to your last point I've quoted above to make it slightly more accurate, hope you don't mind. Lots of people find guesses very helpful - scientists, engineers, police officers being some notable examples. The problem comes when guesses are presented as facts. You'll note in the post I made it very clear that "the following is a guess rather than fact" - not sure how that could be made any clearer.

I've not seen a technical document for an IHD that doesn't display the actual index/register value to be able to understand exactly what data it receives from the meter. It is unlikely that a document detailing the data transfer and processing methods will be in the public domain for either IP or security reasons, but I may be wrong. So until I've seen the kind of information that would confirm the process used I'll keep an open mind on how some IHD's work and what data they are sent. For the time being I'm not going to conclude that engineers designed some IHD's to receive index/register values but then didn't bother with the relatively trivial task of showing that number on a display which they have already designed to be capable of displaying digits. Some designers/manufacturers have done it, so why didn't the others?

Raxiel

While different manufacturers and suppliers may have made different decisions on how to implement the SMETs standard and what information to relay to consumers via the IHD, I feel pretty confident that the Secure Liberty smart meters and IHD that E.ON supplied me with does transmit an actual reading to the IHD. The IHD has a 'meter reading' section in kWh, and the meter itself can display both m³ and kWh, I checked both devices and the kWh figure on both matches, despite the IHD being switched off or out of range occasionally.

It does occur to me that, while neither the meter or IHD knows the correct calorific value to give an exact kWh reading, the notional value they use to provide an 'informative' approximate value is probably fixed. It should only take two or three comparisons of the m³ and kWh readings to figure out what it is (unless you have an IHD that displays that figure as linked earlier in the thread, my own unit doesn't).

From there it wouldn't be hard to convert the kWh reading on the IHD back into an m³ figure for submitting to the supplier monthly for billing. It may not be 100% accurate but i'd be willing to bet it would be +/- 2m³ which isn't going to break the bank. Add in an annual or bi-annual check from the meter itself and it'll all work out in the end anyway.

This wouldn't work for me, because I'd still need to read my electricity meter directly because it's E7 and the IHD only shows the combined figure, also I tend to submit my readings direct to the supplier via the phone while my head is in the cupboard, but It might help those who find the meter hard to reach.

Former_E.ON_Company_Representative:_Malc

Deleted_User wrote: »

Really? That's interesting because I spoke to someone in the billing department of my supplier (E.ON) a couple of months back. She said I should simply convert my in-house display reading from the kWh displayed into cubic meters using a formula she had. Like you, I questioned this saying "surely it depends on caloric value of the gas which varies?". She said no, not so. She had been working for E.ON for 26 years and the conversion formula between cubic meters and kWh had never changed in all the years she had worked for the company.

So you are contradicting what billing staff at E.ON have told me.If that's the case, why don't they do the obvious thing, use some common sense, and let the IHD for gas display the cubic meters exactly matching the meter reading needed by my supplier? What's the point of manufacturing an in-house display which shows meter readings in units which cannot be used for supplying consumer readings and (according to you) are "only an approximation"? They might just as well display the gas reading in Transylvanian Greckles for all the use the displayed figure is.

Hello picks and sorry for the late reply. Missed this post.

I suspect our advisor was talking about the calculation used to convert cubic meters/hundreds of cubic feet into kWh. This hasn't changed in a long time and is explained on our bills.

As others have said, what does fluctuate is the calorific value that forms part of these calculations. This is set by the National Grid on a daily basis and is shared with all the energy suppliers for use on their bills. We take the calorific value figure for each day a bill covers and work out an average. This figure is used in the gas calculation and does vary.

Hope this explains how we use calorific values as part of the calculation to convert gas units into kWh.

Malc

Former_E.ON_Company_Representative:_Malc

brewerdave wrote: »

The EON billing lady is talking thru' her derriere !:rotfl:

I've just looked at a random selection of my EON bills from the last 7 years - the calorific value has been different on all of the bills varying between 39.0 and 39.4:)

As to showing instantaneous cu m on the IHD ? It wouldn't mean anything to the average consumer who only understands KWh.
I do agree that the actual meter reading in cu m should be available by use of a menu of some sort for billing purposes.

As above brewerdave, I'm guessing she was referring to the way we convert gas units into kWh. As you rightly say, the calorific value does vary.

Malc

Former_E.ON_Company_Representative:_Malc

gsmlnx wrote: »

You can get the calorific value from the National Grid website and it does change. The E.ON customer service lady was talking absolute rubbish
http://www2.nationalgrid.com/uk/industry-information/gas-transmission-operational-data/data-item-explorer/
As an example here is the last 7 days for area EA from the website (Note although the date range is up to today due to the way it is calculated in arrears the last full date is for 1 day ago)

Applicable At Applicable For Data Item Value Generated Time Quality Indicator
06/05/2017 10:30:29 06/05/2017 Calorific Value, LDZ(EA) 39.4000 06/05/2017 10:32:01
06/05/2017 10:30:29 05/05/2017 Calorific Value, LDZ(EA) 39.5000 06/05/2017 10:32:01
05/05/2017 10:30:30 04/05/2017 Calorific Value, LDZ(EA) 39.5000 05/05/2017 10:32:01
04/05/2017 10:30:30 03/05/2017 Calorific Value, LDZ(EA) 39.5000 04/05/2017 10:32:02
03/05/2017 10:30:48 02/05/2017 Calorific Value, LDZ(EA) 39.5000 03/05/2017 10:34:01
02/05/2017 10:30:27 01/05/2017 Calorific Value, LDZ(EA) 39.5000 02/05/2017 10:32:01
01/05/2017 10:30:37 30/04/2017 Calorific Value, LDZ(EA) 39.6000 01/05/2017 10:34:01
All data presented on the MIPI and GMRS applications are in GB standard reference conditions. National Grid may receive data for the

gsmlnx wrote: »

The formula is the same BUT the calorific value is a daily variable (and it must be calculated as an average value over the time frame of the bill under OFGEM rules to 1 decimal place)

Please read this post by Hengus where he explains in detail the legal requirements on a supplier to get the calorific value correct
https://forums.moneysavingexpert.com/discussion/comment/72463142#Comment_72463142

As for why the in house display design is so bad, well it is designed by committee to "help" the consumer to understand where their pennies go so an approximation is okay. It is not meant to give 100% accurate values and cannot for gas given everything I and others have said.

Good advice gsmlnx. As you say, we take the calorific value figure for each day a bill covers and work out an average. This average varies. The National Grid gives us this information.

Malc

Former_E.ON_Company_Representative:_Malc

victor2 wrote: »

I look after an account for somebody who has smart meters fitted by EON and even though she is no longer with EON, she can still read her meters from the in-house display EON provided.
Other suppliers publish the details of how to read your meters from the IHDs. Here's two:
https://www.edfenergy.com/for-home/energy-efficiency/smart-meters/home-energy-monitor-detail
https://www.scottishpower.co.uk/pdf/smart-meters/Smart-energy-display-user-guide.pdf

Hello victor2.

Sounds like these smart meters came with a later type of In House Display. Earlier versions of these displays didn't show the meter readings at all and were quickly replaced with a type that did. It's still possible to see the meter readings on these displays after a change of supplier.

Malc

Former_E.ON_Company_Representative:_Malc

Raxiel wrote: »

While different manufacturers and suppliers may have made different decisions on how to implement the SMETs standard and what information to relay to consumers via the IHD, I feel pretty confident that the Secure Liberty smart meters and IHD that E.ON supplied me with does transmit an actual reading to the IHD. The IHD has a 'meter reading' section in kWh, and the meter itself can display both m³ and kWh, I checked both devices and the kWh figure on both matches, despite the IHD being switched off or out of range occasionally.

It does occur to me that, while neither the meter or IHD knows the correct calorific value to give an exact kWh reading, the notional value they use to provide an 'informative' approximate value is probably fixed. It should only take two or three comparisons of the m³ and kWh readings to figure out what it is (unless you have an IHD that displays that figure as linked earlier in the thread, my own unit doesn't).

From there it wouldn't be hard to convert the kWh reading on the IHD back into an m³ figure for submitting to the supplier monthly for billing. It may not be 100% accurate but i'd be willing to bet it would be +/- 2m³ which isn't going to break the bank. Add in an annual or bi-annual check from the meter itself and it'll all work out in the end anyway.

This wouldn't work for me, because I'd still need to read my electricity meter directly because it's E7 and the IHD only shows the combined figure, also I tend to submit my readings direct to the supplier via the phone while my head is in the cupboard, but It might help those who find the meter hard to reach.

Hello Raxiel.

Sounds like you, too, have one of the later types of In House Display we now supply with our smart meters. Unlike earlier versions, these will show the meter readings but, as you say, not the day/night split for Economy 7. Only the total. This is something we're looking at for the future.

Malc