Dial Electricity Meter Reading

[ban-all-sheds]

The method works but you have to start from the right.

Sort-of, but only if one interprets their instruction as meaning:

"If any of the underlined numbers you have written down are followed by a 9 (even if that 9 did not appear until after you had done a "take one away"), you will need to take one away from the number you’ve underlined"

... which is not what I suspect most people would take to mean, but which represents the 'carrying the subtraction to the left' which I mentioned.

Edit: actually, on reflection, I'm not at all sure that it would work in many situations - because I think it probably only works if (as in the OP's situation) the dial 2-to-the left of the 9 is already underlined (i.e. exactly pointing to a number) - whereas 'carrying the subtraction to the left' will, I think, always be needed if one "takes one away" from 0 to get 9.

As I said:

So how do you take 1 away from a digit which is zero, when they do not define any underflow rule?

 

[vards01]

Thanks for all the comments

 

[EFLImpudence]

So how do you take 1 away from a digit which is zero, when they do not define any underflow rule?

It is obvious.

I cannot believe you would think there is any other outcome.
1 less than 60000 is 59999.

I don't think there is any other figure which would have made any real sense.

 

[JohnW2]

As I said:

So how do you take 1 away from a digit which is zero, when they do not define any underflow rule?

Yes, I think we've all agreed (implicitly or explicitly) that the failing of instructions is in not indicating the additional step(s) which are necessary if, by following the instructions such as they are, one "takes 1 away from zero".

Kind Regards, John

 

[ban-all-sheds]

It is obvious.

I cannot believe you would think there is any other outcome.
1 less than 60000 is 59999.

Indeed, but they don't tell you to carry out an operation on the entire number - they tell you to do a series of individual operations on a series of individual digits.

If they followed their instructions you would end up with 69900.

They do NOT tell you that what you have to do is to subtract 1 from 60 to get 59.

They do NOT tell you that you should do multiple passes and re-evaluate digits when an earlier pass has changed the succeeding one.

They do NOT tell you to remove the underscore flag from a digit when you decrement it.


The instructions were written by somebody to whom it was so obvious that 6 0 9 would be transformed to 5 9 9, and not to 6 9 9, or 6 9 9 etc.

In short, it was so obvious to them that they thought they had written what they meant, and didn't bother to read it properly, without assumptions, to check that they really had. Just like some of the posters we get here with their punctuation free blocks of text. They just don't think to see how it reads exactly as written.

 

[EFLImpudence]

That is all true but do we have the actual instructions for the meter company?

Perhaps the OP is reporting what he was told and some was left out leading to the confusion.

All they have to add is that if your adjustment results in another '9' then do the same.
I think treating the digits to the left of a '9' as a whole number would lead to even more confusion were there several '9s', e.g. 69090.



However, the outcome is still obvious otherwise the reading would be lower after using more electricity.

 

[JohnW2]

That is all true but do we have the actual instructions for the meter company? Perhaps the OP is reporting what he was told and some was left out leading to the confusion.

That is obviously a possibility.

However, the outcome is still obvious otherwise the reading would be lower after using more electricity.

Indeed - as we've said, I think the correct answer is obvious, for the reason you give. This discussion is all about the apparent inadequacy of the instructions, assuming that they have been reported to us correctly, and in their totality.

Kind Regards, John

 

[ban-all-sheds]

You can see why they'd have instructions like that. Mechanical pointers are prone to error, and to errors in reading due to parallax. In fact, to me, when you enlarge it, the leftmost pointer does look as though it is just crept past the 6. (Which it would have done were the meter reading 60900 ). But I'm not sure if that's wishful thinking ( ) or where it is pointing, or a parallax error in the photo.

What is wrong with the display is that whatever it's supposed to be reading, the 2nd pointer should not be on 0 when the 3rd is on 9.

I wonder if the alternating direction of the dials is to partially cancel out backlash in the mechanism?

These instructions are much better:

https://www.eonenergy.com/for-your-home/help-and-support/How-to-read-your-meter/Dial-meters

 

[JohnW2]

I wonder if the alternating direction of the dials is to partially cancel out backlash in the mechanism?

Conceivably, but more likely just easier/cheaper - that's what will happen if you just have a straight chain of side-by-side gears, isn't it?

Kind Regards, John

 

[333rocky333]

im quessing the red dials driven anti clock, thus pushing all the other gears as john says