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Supply Overvoltage ignored by DNO

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19K views 49 replies 22 participants last post by  piltdown.boy  
#1 ·
Does anyone know what my next step might be? I have a SYNCEV charger which kept going into fault mode. SYNCEV said that according to their logs this was due to an over voltage of more than 253 volts for more than 3 minutes. I contacted my DNO who came a week later and fitted a monitor. On collecting it a week later they said there was a problem and they would let me know when they had sorted it. Almost 6 weeks later I emailed for an update and was told this had been passed on to the relevant department to lower a transformer tap. After a couple more weeks I emailed this new department and to date have had no reply. I have monitored the voltage myself with a FLUKE multimeter and have got readings of 258.9. I realise this is a peak reading but I also have videos of the meter showing constantly over 254 volts in a socket in my garage. My charger is showing a RED fault LED mode on a daily basis leading to failed charges. Is there any way I can apply more leverage to my DNO?
 
#2 ·
You have an electricity supplier who are charging you for a supply you cannot use.
Speak with them and raise a complaint stating that apart from causing you lost time it is also causing you financial loss.
They have a duty to ensure they only charge you for something you can use and since many charge points would behave in a similar way, the issue needs to be resolved.
Withhold payments as that puts things into perspective for the supplier.

The problem is being a customer doesn't necessarily get you heard so you need to apply pressure where you can.

Best of luck with this.
In the meantime contact evse manufacturers to find out if any are available that would work with your voltages and take advice if they have a solution. Use the cost to have things changed as ammunition to put further pressure on the supplier

Gaz
 
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#3 ·
The DNO have a legal obligation to fix this - they are breaking the law by knowingly supplying you with an out-of-tolerance voltage. The relevant regulation is ESQCR, and is here: The Electricity Safety, Quality and Continuity Regulations 2002

I would point out that you know the regulations and that they are committing an offence by not rectifying the problem. I'd also tell them that you intend to seek damages for damage or loss of functionality to equipment caused by their failure to comply with the regulations.

The specific clause to quote to the DNO is this one (I've highlighted the voltage tolerance). The lower and upper limits of the single phase LV supply voltage are 216.2 VAC and 253 VAC respectively, so anything outside that range is a breach of the regulations:

"Declaration of phases, frequency and voltage at supply terminals

27.—(1) Before commencing a supply to a consumer’s installation, or when the existing supply characteristics have been modified, the supplier shall ascertain from the distributor and then declare to the consumer—

(a)the number of phases;

(b)the frequency; and

(c)the voltage,

at which it is proposed to supply electricity and the extent of the permitted variations thereto.

(2) Unless otherwise agreed in writing between the distributor, the supplier and the consumer (and if necessary between the distributor and any other distributor likely to be affected) the frequency declared pursuant to paragraph (1) shall be 50 hertz and the voltage declared in respect of a low voltage supply shall be 230 volts between the phase and neutral conductors at the supply terminals.

(3) For the purposes of this regulation, unless otherwise agreed in writing by those persons specified in paragraph (2), the permitted variations are—

(a)a variation not exceeding 1 per cent above or below the declared frequency;

(b)in the case of a low voltage supply, a variation not exceeding 10 per cent above or 6 per cent below the declared voltage at the declared frequency;

(c)in the case of a high voltage supply operating at a voltage below 132,000 volts, a variation not exceeding 6 per cent above or below the declared voltage at the declared frequency; and

(d)in the case of a high voltage supply operating at a voltage of 132,000 volts or above, a variation not exceeding 10 per cent above or below the declared voltage at the declared frequency.

(4) The Secretary of State may, following an application by any distributor affected by a declaration made pursuant to paragraph (1), authorise the variation of any of the values or permitted variations contained in a declaration provided that the applicant has previously given notice of his application to such persons and in such terms as the Secretary of State may require.

(5) Where the Secretary of State has authorised a variation under paragraph (4) the distributor shall forthwith serve notice of any such variation on every supplier, other distributor referred to in paragraph (2), and consumer to whom it may apply.

(6) Every distributor shall ensure that, save in exceptional circumstances, the characteristics of the supplies to consumer’s installations connected to his network comply with the declarations made under paragraph (1).

(7) The number and rotation of phases in any supply shall not be varied by the distributor except with the agreement of the consumer or, in the absence of such agreement, the consent of the Secretary of State who may impose such conditions, if any, as she thinks appropriate."


And this is the penalty for their failure to comply:

"Offences

35. Any generator, distributor, supplier, or meter operator or any agent, contractor or sub-contractor of any of the foregoing who fails to comply with any provision of these Regulations which applies to him, any person who fails to comply with regulation 18(3), 21, 22 or 25(1) and any consumer who fails to comply with regulation 8(4) or 34(2) shall be liable on summary conviction to a fine not exceeding level 5 on the standard scale."
 
#6 ·
Having been through this situation recently with SPEN, I got them to ‘pull’ the 30 minute voltage data from my SMETS2 meter. This information was enough to persuade them to fit a voltage monitor which showed voltage in excess of 253 volts. They tapped my local transformer down to a notional 240 volts. I was told that was becoming a big issue for DNOs as more renewables are added to the Grid.
 
#7 ·
Living near a ground mounted rural substation, our incoming L2 (yellow) phase - neutral voltage (we have a 3-phase supply) can at times (usually overnight) exceed 253V, but only occasionally exceeds the old upper limit of 254.4V (240V + 6%). This has so far not caused me any problems (while the car EVSE is connected to the L2 phase, the solar panel inverter is connected to the L1 (Red) phase, which runs a few volts lower).

How critical of the upper 253V upper limit are voltage sensing open-PEN detectors? I would not like one which tripped at anything less that around 260V.

The L2 phase-neutral voltage is consistently higher than the L1 and L3 phase-neutral voltages. Is there any likely reason for this other than unbalanced loading between the phases?
 
#8 ·
How critical of the upper 253V upper limit are voltage sensing open-PEN detectors? I would not like one which tripped at anything less that around 260V.
They MUST trip out if the voltage drops below 207 VAC or above 253 VAC for more than 5 seconds. Nuisance tripping is a complete PITA with these crappy voltage sensing units in rural areas, and they get changed out for proper open PEN fault protection systems with monotonous regularity. I suspect those in the IET that had their arms twisted to allow these crappy bits of kit to be used had zero experience of real-world supplies in rural areas.
 
#10 ·
Glad I spotted this thread. I have the same problem as the OP and have been through the same thing with my SYNCEV charger and Scottish Power Energy Networks.

In my case, after having a discussion with SyncEV, I contacted SPEN. They came and left logging equipment on for a week. The guy told me the supply was regularly exceeding 253. Weeks, if not months later, I was told they had made a change at the transformer. The next day, my SyncEV 'tripped out' and showed red LEDs preventing me from charging. I got back in touch with SPEN who came round and confirmed there was still overvoltage. I still have an outstanding complaint with SPEN. All this took months to play out and we're now almost a year since I first raised the complaint. I've had the same comments as Lexden from SPEN saying that it's not easy to sort out. I have solar panels which they tell me is likely to be contributing to the problem.

I'd given up really but this thread, and the information within it, has encouraged me to get back in touch with SPEN. Thanks to all contributors for their input.
 
#11 ·
Incidentally, I've been speaking to MyEnergi who reckon they have electric wizardry in the Zappi that can deal with overvoltage without causing the same errors that the SyncEV has. I'm tempted to get a Zappi but would rather get the overvoltage issue sorted first. It's also annoying that I may have to shell out for another charge point!
 
#14 ·
MyEnergi use a proper open PEN fault sensing system, so doesn't false trip as all the really crappy voltage sensing things do. Why the IET ever allowed voltage sensing as an option is beyond me, it false trips, and evern worse, it doesn't reliably detect the fault it's supposed to protect against.

I can understand a high-power device such as an EVSE needing to “trip” if the voltage is low, but if the voltage is high, surely cutting off high-power loads only makes the situation worse?
It's the open PEN fault detection circuit false tripping. Companies that use the cheap bodge job voltage sensing option false trip if the voltage goes out of limits for 5 seconds. Those limits are 207 VAC to 253 VAC, and exceeding 253 VAC isn't uncommon, especially if there is a surfeit of PV generation connected to the LV network locally.

I had to rip out an matt-e open PEN fault box of crap a while ago, for exactly this reason, it kept false tripping, making charging fraught with the risk that it would just fail. Converted the installation to TT, having ripped out the matt-e and binned it, and the chap's never had any more problems.
 
#15 ·
Weirdly the last few days every night I plug in and my SYNCEV goes red and shows an error! Resetting in the app doesn't help I have to flip the box next to the meter off then on again... The SYNCEV book suggested it was poor WiFi connectivity so I've rejigged router position... If it does it again tonight I'll ring Sync tomorrow and ask as it might be this, I'd never heard of it before thou!
 
#23 ·
Thumbs up for the Zappi from me. We used to get the very occasional “Over voltage” warning which led to the EV not charging as the Zappi had tripped itself out.
Myenergi updated the firmware. It will still log any such faults but is now less susceptible to tripping out.
Watched a video today about the upcoming changes to EVSE charging delays. Mr Zappi seems quite a cool dude.
He could do with a proper haircut though but if I didn't have my podpoint, I'd likely consider a zappi even though they are a bit ugly.

Gaz
 
#24 ·
As I pointed out in an earlier post, SMETS2 meters do, inter alia, send high voltage warnings. The warnings were explained to me in an email from SPEN late last year:

Quote: My Smart Metering team had a look at your actual smart meter voltage readings over the last 10 days to review the average RMS voltage for every 30-minute period within this time frame. Before I comment on their findings, there are three thresholds of note. These are explained below;

  1. Statutory Voltage Limit (defined in the Electricity, Quality and Continuity Regulation 27) – 253Volts (V)
  2. Smart Meter Over Voltage alarm trigger level – 258V (Statutory Voltage Limit +2%)
  3. Smart Meter Extreme Over Voltage alarm trigger level – 265V (Statutory Voltage Limit +6%, although limited by the smart meter’s maximum voltage reading)
Unquote

I pressed SPEN hard as it wasn't just my EV or Zappi that was tripping out because of high voltages. My Powerwall 2 Gateway would also disconnect my property from the Grid when an over voltage situation was detected. Tesla Support very helpfully provided me with a graph showing the voltages that their system was recording.
 
#25 ·
Just in case anyone else comes accross this post like i did, you can force your SyncEV charger to work above the default 253V cut out as a workaround whilst your DNO investigates like i had to. To do this i setup my charger in the 'monta app', then on a browser (not app) log into monta website and go to your charger. Scroll down to the connection section and click 'view logs', go to "OCPP configuration" tab, click 'get configuration', then edit the "UpperLimitProtectionVoltage" and change from 253 to 260 (wouldnt suggest anything higher as sounds unsafe), tick "save as config override" and "send". All done. To refresh settings on this page click "get configuration" button at top of page again, as otherwise shows previous config of 253V still. hope that helps somebody.
 
#28 ·
We're currently also having over voltage issues.
We get voltage up over 257V at times, it prevents us using our solar. Coffee machine also forgets all it's setting but everything else seems to work OK. The Podpoint doesn't seem to care.

When the voltage is approaching the upper limit the inverter will not raise the voltage above the limit, hence we lose the ability to self consume either solar or battery. Our GivEnergy inverter seems to handle this reasonably gracefully, in that there are no dramas or alarms, it just doesn't raise the voltage above 253V (so we lose some or all of our ability to self consume but it holds at 253V to use as much as we can if the voltage is still under 253). It then resumes full output without complaints when the voltage drops again.

We can also see the grid voltage in the GE data and can display it on a graph. Took a while to figure this out but once we found the grid voltage everything becomes clear.

Bloody annoying though. You plug the car in to the granny, or stick the immersion on because it's a sunny day, only to see later on that your actually pulling from the grid rather than running on solar and battery. We've yet to have a day of full solar output regardless of having had days with crystal clear blue skies.

The DNO have now fitted a voltage recorder for the week. Looks like we were 2 hours over 253V out of 24 hours so far.
 
#31 ·
We're currently also having over voltage issues.
We get voltage up over 257V at times, it prevents us using our solar. Coffee machine also forgets all it's setting but everything else seems to work OK. The Podpoint doesn't seem to care.

When the voltage is approaching the upper limit the inverter will not raise the voltage above the limit, hence we lose the ability to self consume either solar or battery. Our GivEnergy inverter seems to handle this reasonably gracefully, in that there are no dramas or alarms, it just doesn't raise the voltage above 253V (so we lose some or all of our ability to self consume but it holds at 253V to use as much as we can if the voltage is still under 253). It then resumes full output without complaints when the voltage drops again.

We can also see the grid voltage in the GE data and can display it on a graph. Took a while to figure this out but once we found the grid voltage everything becomes clear.

Bloody annoying though. You plug the car in to the granny, or stick the immersion on because it's a sunny day, only to see later on that your actually pulling from the grid rather than running on solar and battery. We've yet to have a day of full solar output regardless of having had days with crystal clear blue skies.

The DNO have now fitted a voltage recorder for the week. Looks like we were 2 hours over 253V out of 24 hours so far.
This is very annoying and doubly frustrating because the DNO aren't interested about fixing a situation that is outside the spec they are mandated to maintain. The problem will be that there are a few houses on the same transformer as you at the very end of a too-long too-thin LV cable who were getting low-voltage and the cheapest way to fix it was for the DNO to retap the transformer and give those closeby over-voltage.

You can upgrade the cable between your CU and the inverter. for example if you swap a 4mm² for a 6mm² the inverter will have to raise the Voltage less to push the same power. This is more effective if the cable from your inverter to CU is more than a few metres.

You should also be very careful about upgrading your EV charging point, because another model might refuse to work in the over-voltage condition.
 
#30 ·
Settings in the inverter should be adjustable, if not by you then by the installer, to prevent the problems you are having.
Well we could raise the voltage limit in the inverter settings, the UKPN engineer actually suggested this also. If I raise my output limit above 253V then surely I am creating overvoltage problems for others or at least making them worse. And then I'm also breaching the regs.
I'd far rather the DNO supplied 225-240V, rather than try and deal with 240-257 by raising it further for everyone else, and testing everyone else's devices to see which ones survive high voltages. Doesn't seem like the best solution if I can get the DNO to turn it down a notch.
 
#38 ·
There is work afoot in my local area next week and I contacted SPEN on the number given. Apparently the transformer that feeds my side of the village will be changed as part of all the other work (new overhead lines, poles etc) so I'm hoping this will resolve the high voltage issue I have.
 
#42 · (Edited)
You are wasting your time getting either the EV charger supplier or the DNO to help you. The reason for this is because they all have tolerance they need to work to I have this happen a lot especially with Proteus who are a Uk company and should know better but the same applies to them all to be on the safe side I think they all fault out at significantly less that 253 volts and they all use cheap electronics which will measure an AC voltage to +/- 1 % so I have seen switch out as low as 243 Volts so they have to switch out well below 253 to make them complaint. I have a good work around using a fluke calibrated multi meter Last week a came across one which had been in for a couple of years and started with this fault with an ac supply on 245 volts. so i installed a transformer British General Fortress 8-24V AC 8VA Bell Transformer Module (8707P) under £10 from screw fix or a
VEMER VN316600 model TMC 15/12 Just make sure its double insulated and does not require an earth

I used the 8 volt output to subtract 8 volts from the 245 volts just for the VMD01F voltage module making it 237 volts and the problem whent away So long as you are sure your voltmeter is reading correctly you can be sure the unit will still cut out with less than 253 volts so all is safe The VMD01F does not consume enough power to overload either the primary or the secondary of the transformer
,

With this solution its not even worth complaining to anyone as you will get no help so I get on with it and the customer is very happy and wont believe you anyway when you try to blame someone else while he is suffering
Image
 
#44 ·
Boy this is indeed frustrating. I think after reading this string I have all the issues noted!! Our over voltage was reported by my neighbour last year when his car charger stopped working. They fixed his issue by moving his supply point from the grid. It would require a lot of cable to do the same for us being in a rural area. Our over voltage seems to fluctuate along with solar panel generation as well as early mornings when the use is generally low. They cant easily change our transformer tapping as it will lower the voltage to houses up the street.
Since they were notified of the issue by my neighbour last year they have not solved the general issue just a sticky plaster on the single house case. We are holding off on our EV charger instal as our heat pump inverter fried during commissioning due to the over voltage. Its been 6 weeks now since they confirmed they still have an over voltage issue and now they are quoting the 6month clause to me before a fix! I am holding up two lots of installers at my cost and am looking at what I can do to regulate the supply correctly although nothing is cheap. I have contacted the Consumer protection agency and am awaiting a reply. If I treated customers with this cavalier attitude when I was working it would have been a short career.
 
#45 ·
Boy this is indeed frustrating. I think after reading this string I have all the issues noted!! Our over voltage was reported by my neighbour last year when his car charger stopped working. They fixed his issue by moving his supply point from the grid. It would require a lot of cable to do the same for us being in a rural area. Our over voltage seems to fluctuate along with solar panel generation as well as early mornings when the use is generally low. They cant easily change our transformer tapping as it will lower the voltage to houses up the street.
Since they were notified of the issue by my neighbour last year they have not solved the general issue just a sticky plaster on the single house case. We are holding off on our EV charger instal as our heat pump inverter fried during commissioning due to the over voltage. Its been 6 weeks now since they confirmed they still have an over voltage issue and now they are quoting the 6month clause to me before a fix! I am holding up two lots of installers at my cost and am looking at what I can do to regulate the supply correctly although nothing is cheap. I have contacted the Consumer protection agency and am awaiting a reply. If I treated customers with this cavalier attitude when I was working it would have been a short career.
Sounds like you might take the advice of those who turned the screw a bit harder by contacting ofgem or threatening to do so. If the overvoltage is caused by solar... who's is it? Ours was set up to respect the 253V limit. I know others will push their limit higher to allow them to use more of their solar, but that will just cause problems for everyone else on the same phase.
 
#46 ·
it takes rather a long time for a massive organisation like a DNO to react to new situations and change. There are even fewer ‘Vol rise savvy” executives and managers” than there are engineer specialists and network analysts within the DNO’s. And it’s NOT about money; There’s colossal funding available to reinforce circuits for Low Carbon Tech, but there are also old fashioned mentalities and approval processes to get at the funding. There’s all sorts of established resistance to gear up to change, but it’s not about lack of capital funds, there’s plenty of that already stumped up by UK government.The bottleneck or restriction is getting DNO’s up to speed to identify circuit problems, then devise a future proof solution, then actually get the job scheduled against societal pressures like “you’re not digging our street up again are you” But public disruption is just one factor. At the moment, understanding, manpower and skills are probably the primary obstacle.
 
#47 ·
It's my understanding that one of the methods for open PEN protection requires an EV charger to measure incoming voltage and cut out if the voltage exceeds 253V or falls below 216V. It's unclear to me why the upper threshold is important but in any case if you do change that voltage you are potentially disabling a safety function.
 
#48 ·
At the previous house, an old railway station on the end of a rural farm type supply the voltage was ~250v. This meant that every so often the PV inverter would shut off so had to devise a method of monitoring. Things did improve over time but that was down to local infrastructure/lines being replaced. Cheers!
 
#49 ·
In an Open PEN situation where the neutral conductor is open circuit between you and the substation a high voltage can occur if your phase is not taking as much current as the other two phases. The opposite occurs when your phase is taking more than the other two.

In an ideal world the load on each of the three phases is equal and no neutral current needs to flow back to the substation. When its out of balance with an Open PEN your neutral/earth voltage (the body of the car) is not the same as the local earth voltage giving rise to a shock risk with someone coming into conact with your car. Its a RIDDOR reportable fault and there were 400 of these in 2019 resulting in about 40 cases where injury was caused if I remember correctly.