Landis GYR+ E470 Type 5394

Chris_b2z

It's a bit of a long shot, but the Landis+Gyr E470 User Manual suggests that the Event Log can be accessed from the customer menu. Hopefully, it hasn't been cleared or wrapped around. It would be interesting to see if there were any entries around the dates in question.

mmmmikey

Apologies if I've missed something in an earlier post, but I wonder if it's possible that this is a problem that is upstream somewhere from the meter - e.g. the meter itself is fine but the billing is based on data from someone else's meter due to an admin issue in the billing system? If you haven't done so already it's worth checking that the readings on the meter correspond to the readings on the bills.

BarelySentientAI

victor2 said:

You would like to think that somebody in a position at the supplier to actually think about those readings would realise they cannot possibly be true.

Take 03/01/2024 from 00:30 to 01:00, where the meter reported usage of 16.653kWh. That's an average of 138.8A at 240V for the 30 minute period. Aren't those meters rated at 100A maximum?

I have no idea how those meters work, but is it at all possible for some sort of external influence to cause them to generate false readings? Unfortunate in a way, that the problem hasn't obviously repeated itself since January, and presumably a meter test now would indicate it is working just fine.

I have several theories how - some of which I can replicate and some I can't yet. 

Most result in a sudden step change to the meter, not a long period of high readings, but a couple could theoretically result in what's happened here. 

Have been used previously to include a high electricity bill in an insurance claim.

Qyburn

Reed_Richards said:

I find myself wondering how much electricity it is possible for you to use?  If you turned on your oven, all the rings on your hob, your immersion heater and a couple of fan heaters would even that get you up to 14 kW?  

It was recording 14kWh in 1/2 an hour, that's 28kW.

Reed_Richards

Qyburn said:

Reed_Richards said:

I find myself wondering how much electricity it is possible for you to use?  If you turned on your oven, all the rings on your hob, your immersion heater and a couple of fan heaters would even that get you up to 14 kW?  

It was recording 14kWh in 1/2 an hour, that's 28kW.

Yes, you're absolutely right.  Apologies, silly of me.  I just can't get my head around any set of circumstances that could possibly draw so much power in any normal house or anything that could cause an electricity meter to give false readings for a few days before going back to normal.

Reed_Richards

I've been racking my brains about this one.  The only thing I came up with was a memory that this meter had had reported issues associated with a moving decimal point, that the number of digits after the decimal point had changed in a few cases.  Seemingly this would only apply to manual readings but the cause appeared to be a remotely applied update to the meter software.  Could it be that there was some wrong remote "update" applied to this meter that was pulled a few days later?    

victor2

Reed_Richards said:

I've been racking my brains about this one.  The only thing I came up with was a memory that this meter had had reported issues associated with a moving decimal point, that the number of digits after the decimal point had changed in a few cases.  Seemingly this would only apply to manual readings but the cause appeared to be a remotely applied update to the meter software.  Could it be that there was some wrong remote "update" applied to this meter that was pulled a few days later?    

But such an issue wouldn't result in a sequence of high readings, would it? 

BarelySentientAI

Reed_Richards said:

I've been racking my brains about this one.  The only thing I came up with was a memory that this meter had had reported issues associated with a moving decimal point, that the number of digits after the decimal point had changed in a few cases.  Seemingly this would only apply to manual readings but the cause appeared to be a remotely applied update to the meter software.  Could it be that there was some wrong remote "update" applied to this meter that was pulled a few days later?    

My theory is to do with saturation of the measuring circuit from electrical "noise" on the grid.  I've seen sudden voltage changes make a meter jump up, but that can't have happened here as it's a continuous high reading, so I'd be leaning towards considering a high harmonic current contribution making the measurement circuits incorrectly interpret the power-frequency current.

They're only tested for accuracy at a set range of harmonic contributions (a little wider than what are actually allowed on the system), so if there was a persistent harmonic source causing the local contributions to be driven above the allowable range, perhaps this could have caused a longer period of "running too fast".

Most other faults are transient (or very short term) but harmonics can be persistent across longer periods.

Reed_Richards

I have no idea @victor2, my theory is pure conjecture.  I imagined a meter getting a bad software update that would cause all subsequent readings to be wrong.  But then this update is rescinded a few days later.  In this imaginary scenario, somebody in the Smart Meter division of the supplier makes a mistake and sends the meter the wrong software or a corrupt update.  A few days later they realise their mistake and set the meter back to the way it was before.  But they don't want to get into trouble so don't report what they did.   

WBCPB

BarelySentientAI said:

a high harmonic current contribution making the measurement circuits incorrectly interpret the power-frequency current.

Qué ???????