we are getting a lot of properties with high grid voltage, (over 253 VAC) usually we find that it is just over 250 VAC but it creeps up as the day get brighter with the various solar installations in the area churning our more kw. we have one customer who is getting 256VAC on a good day, not just at the inverter but right at the main incoming, the DNO has been twice to measure the voltage but he conveniently only turns up about 7pm when everyone's solar is ramping down and there is more demand on the grid with cooking etc, etc, we usually find it is single phase installations but a three phase site is getting this issue at the moment,
grid voltage
- Thread starter f0ster
- Start date
spark plug
Member
The tolerance on the grid is 230v +10% -6%, so anything between 216v and 253v is acceptable.
Solar feeds into the grid by using a slightly higher voltage than the grid, but if the grid is already near the upper tolerance then you could go past the upper threshold.
Are you having problems with anything? Generally you don’t see any issues.
Solar feeds into the grid by using a slightly higher voltage than the grid, but if the grid is already near the upper tolerance then you could go past the upper threshold.
Are you having problems with anything? Generally you don’t see any issues.
Netherfield
Member
- Location
- West Yorkshire
242 V here at present, early mornings and later at night it can get to 250 V.
Nothing to worry about though.
UK used to be 240 V nominal, then to 'harmonise' with the EU it went down to 230 V, Distributors couldn't go round changing every transformer on the network, so basically nothing changed.
Looking back to old Motor plates single phase would have 220-250 V and three phase 380-440 V stamped on them.
Higher the voltage reduce the amperage or vice versa bu the wattage stays the same.
Nothing to worry about though.
UK used to be 240 V nominal, then to 'harmonise' with the EU it went down to 230 V, Distributors couldn't go round changing every transformer on the network, so basically nothing changed.
Looking back to old Motor plates single phase would have 220-250 V and three phase 380-440 V stamped on them.
Higher the voltage reduce the amperage or vice versa bu the wattage stays the same.
Last edited:
- Location
- North Norfolk
Keep reporting voltages over 253 and the time of day. Keep a record of the reference numbers for the reports. If you nag them enough they should fit a voltage recorder to look for peaks and troughs. Which DNO? Some are more helpful than others.
Can you get a voltage log off the inverters to submit to them? That would help.
Do the inverters drop out at over 253? Our G59 relay does, but there is a more sensible lag than there was before the upgrade.
Timbo
Member
- Location
- Gods County
Depends on what the Inverter has been set to, although default on most of them is 258v, could be set as high as 265v though...
Exfarmer
Member
- Location
- Bury St Edmunds
Yes you have to keep at the DNO. I would not be too concerned at 260 volts but of course your inverters should shut down if the voltage exceeds 253. Your supplier should be aqble to change the settings in the inverter to alloow higher voltages. I have seen 305 volts on one phase thanks to a neighbour installing 30Kw arrayt on a single phase supply . Not sure how he got permission for it
the DNO has a legal obligation to rectify any installations where the voltage exceeds 253 VAC, but what we are getting now is (ohh it is only above 253 VAC occasionally so it will be ok) if the DNO wont do anything the fix for this is easy enough, you have a solar installation that is producing a fraction of what it should be and inverters do not produce a fault code for this fault because it is not a fault of the inverter, it just shuts down and does a reboot, on start up if the voltage is back down below the uk spec it then start up again, the customer might never get to know it is doing this because it does not create any fault code, some times the DNO has been able to wind down the transformer if it is not too old but quite often it is an old type and requires replaced,
the UK tolerance of 216-253 is becoming meaningless and the DNO does not want to have to keep replacing transformers, to fix this you have to change the country code or not set it at all,
the UK tolerance of 216-253 is becoming meaningless and the DNO does not want to have to keep replacing transformers, to fix this you have to change the country code or not set it at all,
Exfarmer
Member
- Location
- Bury St Edmunds
It is a good leverage if you are wanting a gris upgrade suxch as a larger supply
- Location
- Burton on trent
for about a year our CHP kept tripping out, grid voltage was around 253/255 at times, sometimes higher.
I had quite a fight with the WPD about it at the time. The chp data showed the high voltage, and sent them the data, but they would not do anything, I told them you are legally bound to sort this.
In the end they left a datalogger on the connection for about a week or 2.
When they returned and read the logs, the guys said 'we will be here in a couple of days to turn the transformer tap down'
I had quite a fight with the WPD about it at the time. The chp data showed the high voltage, and sent them the data, but they would not do anything, I told them you are legally bound to sort this.
In the end they left a datalogger on the connection for about a week or 2.
When they returned and read the logs, the guys said 'we will be here in a couple of days to turn the transformer tap down'
- Location
- SG9
@Exfarmer a question you may be able to answer or others.
My F House is on 3 phase but everything used is single phase split over the phases not overly equal as Air Source is the only thing on one of the Phases and I am aware this is my major annual user.
Am thinking of putting a fresh/new solar array on this property of 10Kw.
The Question, should I put solar out put on the 3 phases and if so would the say. 6Kw output over 3 phases balance out to a Zero record on the meter reading if the solar was using 6Kw.
Hoping you all get the drift of what I am asking.
My F House is on 3 phase but everything used is single phase split over the phases not overly equal as Air Source is the only thing on one of the Phases and I am aware this is my major annual user.
Am thinking of putting a fresh/new solar array on this property of 10Kw.
The Question, should I put solar out put on the 3 phases and if so would the say. 6Kw output over 3 phases balance out to a Zero record on the meter reading if the solar was using 6Kw.
Hoping you all get the drift of what I am asking.
- Location
- Burton on trent
not sure the current situation, but in the past, I've seen it when I've been exporting on 2 phases and importing on 1 phase.
They then charged me, what ever the rates were against each.
so the importing phase might be say 30p and I'm only exporting at 10p on the other 2 phases.
So balancing this out, definitely can save money.
They then charged me, what ever the rates were against each.
so the importing phase might be say 30p and I'm only exporting at 10p on the other 2 phases.
So balancing this out, definitely can save money.
Exfarmer
Member
- Location
- Bury St Edmunds
Sorry I do not know the answer but suspect @rollestonpark is correct
- Location
- Northumberland
To counter this, I was assured by a WPD (who supplied my meter) techie that this shouldn't happen as the aggregation sequence netted the phases first.
I still have lingering doubts, but have never found any evidence.
- Tags
- drift