Gas meter calculation

[ohdearme]

Hello all,

 

I am a non science person, just joined. Can some kind person help me find out what the circular dial on the right side of my Imperial digital Parkinson Cowan gas meter represents. Kwhs? units? While researching the internet for an answer, I have come across abbreviations: 1 eu.tt and cu.tt (oxfordshire.gov.uk/cms/sites...website). What are these please?

 

I would be most grateful for help and if you don't mind, could you please tell me where to find my post when I log in to get any answers.

Regards

 

Alan

 

[Strange]

Doesn't it say on the meter? For example, this one says cubic feet:

http://farm1.static.flickr.com/172/383552656_19b69848be_b.jpg

 

(I have no idea what eu.tt or cu.tt might be)

Did you, perhaps, misread cu. ft. (cubic feet) as cu. tt. ?

[Greg H.]

Typically gas meters read in cu ft, which is, as Strange pointed out an abbreviation for cubic feet.

[ohdearme]

Yes thank you for replying, however the dial on the right does not seem to reconcile with the digital read out. Is it Kwh? does not seem to be.

Regards

Alan

[studiot]

No gas meter reads kilowatt-hours.

 

Gas meters measure the flow of the gas.

 

Usually they measure the total volume of gas that has passed through the meter since it was set in place.

 

As has already been observed this is normally in cubic feet, I do not know of any that are metric, though I suppose the Europeans must have them.

 

Measurements are taken by noting the difference over a specific period.

 

The last digit or dial is only read when testing apparatus or seeking leaks.

 

Once you have the volume of gas that has passes by subtracting an earlier reading from a later one you convert this to a nominal maximum energy by multiplying this volume by the stated calorific value of the gas supplied. All companies by UK law must state this value in their bills.

The calorific value varies slightly from day to day.

 

The gas company normally perform this calculation for you and also convert to the metric unit of kilowatt-hours.

 

You should also know that this is the theoretical maximum energy available in the gas.

 

No apparatus is 100% efficient so you will never obtain this figure.

[Greg H.]

Yes thank you for replying, however the dial on the right does not seem to reconcile with the digital read out. Is it Kwh? does not seem to be.

Regards

Alan

It would probably help a lot if you could attach a photo of the readouts in question.

[StringJunky]

It seems to me the dial is for showing a more sensitive real-time indication of gas usage - one revolution equals 1 cu.ft

 

Here's a Parkinson:

 

 

Here's British Gas one:

 

 

Seems to be a standard indication

Edited October 30, 2014 by StringJunky

[studiot]

Good pics SJ, they show my points well. +1

[StringJunky]

Thanks

[Greg H.]

For comparison, here's a standard American one:

 

Edited October 30, 2014 by Greg H.

[StringJunky]

Greg H., on 30 Oct 2014 - 5:50 PM, said:

For comparison, here's a standard American one:

 

Interesting. Still not digital yet then.

 

Does ambient temperature affect the accuracy of flow meters in terms of the amount of gas actually delivered through changes in pressure caused by it or does the pumping station compensate for this?

 

 

[Greg H.]

Interesting. Still not digital yet then.

 

Does ambient temperature affect the accuracy of flow meters in terms of the amount of gas actually delivered through changes in pressure caused by it or does the pumping station compensate for this?

According to the wikipedia article on them,

 

 

 

Gases are more difficult to measure than liquids, as measured volumes are highly affected by temperature and pressure. Gas meters measure a defined volume, regardless of the pressurized quantity or quality of the gas flowing through the meter. Temperature, pressure and heating value compensation must be made to measure actual amount and value of gas moving through a meter.

So it appears there must be some kind of compensation going on somewhere.

Edited October 30, 2014 by Greg H.

[StringJunky]

Greg H., on 30 Oct 2014 - 7:20 PM, said:

According to the wikipedia article on them,

 

 

 

 

So it appears there must be some kind of compensation going on somewhere.

Right. Cheers.

[Strange]

Yep, Googling gas meter compensator brings up lots of results (including several patents) for temperature compensation.

[JonG]

Just in case it has't already been mentioned, the kilowatt hour (kWh) is a unit of energy. In my case, the conversion from volume of gas used to kWh is given on my gas bill, for example;

 

"Units used = 20 m³, kilowatt hours = 219"

 

I have a smart meter and cubic feet don't appear anywhere on it. If I do read it, the reading is in m³.

[Strange]

It seems to me the dial is for showing a more sensitive real-time indication of gas usage - one revolution equals 1 cu.ft

 

Here's a Parkinson:

gas meter.PNG

 

Yes thank you for replying, however the dial on the right does not seem to reconcile with the digital read out.

 

In the Parkinson meter in that picture, it looks as if the dial would have to go round ten times for the reading to change (because the last (units) digit is painted on the display).

[StringJunky]

Strange, on 31 Oct 2014 - 12:17 PM, said:

 

 

In the Parkinson meter in that picture, it looks as if the dial would have to go round ten times for the reading to change (because the last (units) digit is painted on the display).

It's just for testing.

[Strange]

It's just for testing.

 

But surely it goes round in normal use, doesn't it? (I was just trying to understand/explain the "reconcile" comment.)

[StringJunky]

I read on a supplier's site to ignore the last dial because it is for testing. Perhaps it is isolated mechanically to give an independent measure. I'm only guessing here but the general theme of my enquiries is that it should be ignored from a consumer perspective. No harm in wanting to know why though.

[Strange]

I read on a supplier's site to ignore the last dial because it is for testing. Perhaps it is isolated mechanically to give an independent measure.

 

That's possible. It may show the uncompensated flow. Or maybe it is only active for high flow rates. Or ... <shrug> Thanks for clarifying.

Edited October 31, 2014 by Strange

[StringJunky]

Found a forum conversation with someone that seems to know who's a gas appliance diagnostics technician.

 

QuoteQuote

 

...Anyway, the half foot dial is commonly refered to as the test dial. If all the pilots where turned off and no appliances where on, that test dial can be used to determine if any gas leaks where present.

If the dial pointer cannot remain fixed in one spot on the dial for a minimum of two minutes, it can be determined that a leak exists. The point hand must be in the up stroke and it must remain it a fixed set position for that period of time.

The test dial is used for this pupose by trained gas company service persons to determine if leakage exists. The 2 foot dial is more commonly used to determine if an appliance is operating at it's set BTU rating.......

 

http://www.doityourself.com/forum/gas-oil-home-heating-furnaces/117158-gas-meter-reading.html

Edited October 31, 2014 by StringJunky

[ohdearme]

It was me that started this post which seems (happily) to have enlarged somewhat.

Thank you all, it's good to know that people will help others.

 

Best to all of you.

 

Alan

Thanks for this everyone, you helped me with my initial question which seems (happily) to have expanded.

 

Best to all.

Alan