255v - stopping ev charger

[UNG]

With mains voltages continuing to rise above the 253v upper limit and given that the +10% -6% is a statutory requirement detailed in the ESQCR who is the enforcing body. A quick skim read of the ESQCR puts some reportable parts within the HSE's remit but it is not clear who would enforce over voltage supply issues unless someone is injured. I can only assume that OFGEM who issue the operating licences for the DNO's would be the enforcing authority, so do we need to start raising complaints to OFGEM where DNO's continually do nothing to fix ongoing overvoltage problems

 

[ruggedscot]

With mains voltages continuing to rise above the 253v upper limit and given that the +10% -6% is a statutory requirement detailed in the ESQCR who is the enforcing body. A quick skim read of the ESQCR puts some reportable parts within the HSE's remit but it is not clear who would enforce over voltage supply issues unless someone is injured. I can only assume that OFGEM who issue the operating licences for the DNO's would be the enforcing authority, so do we need to start raising complaints to OFGEM where DNO's continually do nothing to fix ongoing overvoltage problems

doesnt have to injure,,, the higher voltage can be considers as a fire risk.... etc.

they are duty bound to maintain the voltage within specification, on all loads. sounds like they have a customer thats going below voltage someplace, and they are trying to keep that from happening, and when the system is low loaded the voltage is higher.

where is the local transformer, does it have a manual or auto tap changer. the 11kv system what does that feed how many consumers and area covered.... what about that ? maybe thats where the issuer lies on the 11kb side hence its a headache to the utility.

 

[UNG]

doesnt have to injure,,, the higher voltage can be considers as a fire risk.... etc.

they are duty bound to maintain the voltage within specification, on all loads. sounds like they have a customer thats going below voltage someplace, and they are trying to keep that from happening, and when the system is low loaded the voltage is higher.

As HSE generally only deal with cases where people have suffered injury or are working unsafely would they use their enforcement powers under ESQCR as over voltage is not a reportable incident

Yes I agree that over voltage as can under voltage contribute to an increased fire risk but that was not the point I was making which was who is responsible for enforcement of the ESQCR

where is the local transformer, does it have a manual or auto tap changer. the 11kv system what does that feed how many consumers and area covered.... what about that ? maybe thats where the issuer lies on the 11kb side hence its a headache to the utility.

I don't think you have read all of this thread one of the big problems is the DNO's have never really acted on the voltage harmonisation changes back in the 90's even when updating the distribution network

 

[RogTP]

I’m awaiting action from the DNO. They have backed off from enforcing my line for two reasons. Firstly it would likely increase voltage through lower impedance, and existing impedance is within spec.

The pole transformer is manual tap, so they would need to do some sort of switch off to reduce voltage. I understand that whilst there are only relatively few of us on the pole, the 11k switch off would be quite substantial.

 

[ruggedscot]

As HSE generally only deal with cases where people have suffered injury or are working unsafely would they use their enforcement powers under ESQCR as over voltage is not a reportable incident

Yes I agree that over voltage as can under voltage contribute to an increased fire risk but that was not the point I was making which was who is responsible for enforcement of the ESQCR

I don't think you have read all of this thread one of the big problems is the DNO's have never really acted on the voltage harmonisation changes back in the 90's even when updating the distribution network

have not read the whole thread ? tad presumptious on your part.... well aware of the harmonisation. and for the reasons behind it. all mains electrical equipment designed for europe must be able to work on the range of that tolerance. As the uk meets that range it does not need to be 230v.

Your Electricity Board by law must deliver 230 volts +10% – 6% (ie. between 216.2 volts and 253 volts), and to maintain the frequency at 50Hz ± 1% (ie. between 49Hz and 51Hz) over a 24 hour period.

The EU decided, in its wisdom, to harmonise the UK standard mains voltage of 240v AC and the European standard of 220v AC, at 230v AC. Fine in theory but the costs of replacing all the supply equipment to deliver 230v was uneconomic (there being no advantage whatever in changing, other than ‘harmonisation’). So to avoid accusations of failure to harmonise, they simply fiddled with the legal voltage limits, nothing actually changed!.

The law now states 230v +10% -6%, thereby allowing the European 220v system to stay at 220v and UK to stay at 240v, yet both appear to be harmonised!

https://www.se.com/uk/en/faqs/FA144717/
The issue with the OP is that his local area network is serving a larger area. this is giving cause for the wide voltage. He will be near the grid to distribution transformer, the one with the auto tap changers, and the 11kv getting adjusted will mean his 11kv to 400v transformer will be affected. Grid really needs to sort out the local 11kv network

 

[UNG]

have not read the whole thread ? tad presumptious on your part.... well aware of the harmonisation. and for the reasons behind it. all mains electrical equipment designed for europe must be able to work on the range of that tolerance. As the uk meets that range it does not need to be 230v.

So you are covering very very old ground

Your Electricity Board by law must deliver 230 volts +10% – 6% (ie. between 216.2 volts and 253 volts), and to maintain the frequency at 50Hz ± 1% (ie. between 49Hz and 51Hz) over a 24 hour period.

So we know it is law my comment was who is the enforcement authority to ensure this happens

The EU decided, in its wisdom, to harmonise the UK standard mains voltage of 240v AC and the European standard of 220v AC, at 230v AC. Fine in theory but the costs of replacing all the supply equipment to deliver 230v was uneconomic (there being no advantage whatever in changing, other than ‘harmonisation’). So to avoid accusations of failure to harmonise, they simply fiddled with the legal voltage limits, nothing actually changed!.

The law now states 230v +10% -6%, thereby allowing the European 220v system to stay at 220v and UK to stay at 240v, yet both appear to be harmonised!

https://www.se.com/uk/en/faqs/FA144717/

Yet more old ground covered that I believe that was first seen circa 1995. At the time it was announced Manweb ran some contractor events and reckoned it would take around 30 to 50 years before the voltage came down closer to 230v across the local network as the distribution equipment was updated or replaced

The issue with the OP is that his local area network is serving a larger area. this is giving cause for the wide voltage. He will be near the grid to distribution transformer, the one with the auto tap changers, and the 11kv getting adjusted will mean his 11kv to 400v transformer will be affected. Grid really needs to sort out the local 11kv network

Since when has the grid been responsible for the 11Kv network. The 11 and 33Kv networks are the responsibility of the local DNO

 

[Richard-the-Ninth]

Gentlemen, it looks very much like you will never agree on anything, arguing between yourselves does not help the OP with his question. Please bear this in mind, I don't like to use the delete button.