I became aware of low voltage @ 1700hrs yesterday. ~228Vac instead of the usual 240 to 245Vac.
Still low @ 1900hrs.
Reported the problem to Scottish Power via their enquiries line @ 1905hrs.
Two technicians on site @ 2025hrs.
Recorder due to be fitted today at 1130hrs.
That is exemplary service.
Well done Scottish Power.
Still low @ 1900hrs.
Reported the problem to Scottish Power via their enquiries line @ 1905hrs.
Two technicians on site @ 2025hrs.
Recorder due to be fitted today at 1130hrs.
That is exemplary service.
Well done Scottish Power.
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I thought its 230V in the UK nowadays, at least Wikipedia says so:
Mains electricity by country - Wikipedia, the free encyclopedia
has to do with the EU "voltage harmonization":
Mains electricity - Wikipedia, the free encyclopedia
"Following voltage harmonization, electricity supplies within the European Union are now nominally 230 V ± 10% at 50 Hz.[1] For a transition period (1995–2008), countries that had previously used 220 V changed to a narrower asymmetric tolerance range of 230 V +6% −10% and those (like the UK) that had previously used 240 V changed to 230 V +10% −6%.[2] No change in voltage is required by either system as both 220 V and 240 V fall within the lower 230 V tolerance bands (230 V ±10%). Some areas of the UK still have 250 volts for legacy reasons, but these also fall within the 10% tolerance band of 230 volts. In practice, this allows countries to continue to supply the same voltage (220 or 240 V), at least until existing supply transformers are replaced. Equipment (with the exception of filament bulbs) used in these countries is designed to accept any voltage within the specified range."
Mains electricity by country - Wikipedia, the free encyclopedia
has to do with the EU "voltage harmonization":
Mains electricity - Wikipedia, the free encyclopedia
"Following voltage harmonization, electricity supplies within the European Union are now nominally 230 V ± 10% at 50 Hz.[1] For a transition period (1995–2008), countries that had previously used 220 V changed to a narrower asymmetric tolerance range of 230 V +6% −10% and those (like the UK) that had previously used 240 V changed to 230 V +10% −6%.[2] No change in voltage is required by either system as both 220 V and 240 V fall within the lower 230 V tolerance bands (230 V ±10%). Some areas of the UK still have 250 volts for legacy reasons, but these also fall within the 10% tolerance band of 230 volts. In practice, this allows countries to continue to supply the same voltage (220 or 240 V), at least until existing supply transformers are replaced. Equipment (with the exception of filament bulbs) used in these countries is designed to accept any voltage within the specified range."
Its strange when you notice a sudden change presumably after years of knowing what you normally measure and yes I know we are on 230 vac nominal officially.
Could be many reasons (not windy enough
)
What is revealing is seeing how well it stands up under load. We had such an issue some years back. Off load was fine at 245 or so, on load, say 80 amps (we are all electric with storage heaters) and I could pull it down to 216. Mentioned it to Norweb (I worked for them at the time but not on the mains side of things) and they gave me a chart recorder to plug in at home to record what was happening. There was no hassle, after a couple of days I took the recorderback and they said it was because we were a high user and at the end of the line. They came and back fed (that's connected in parallel) as a temporary measure from the end of the road to another sub stations output in the next road. Some days later they severed the original supply about two thirds of the way down the road so the end houses were now all fed from the higher capacity main. No problems since. No interupptions to supply either, all worked on live.
Could be many reasons (not windy enough
) What is revealing is seeing how well it stands up under load. We had such an issue some years back. Off load was fine at 245 or so, on load, say 80 amps (we are all electric with storage heaters) and I could pull it down to 216. Mentioned it to Norweb (I worked for them at the time but not on the mains side of things) and they gave me a chart recorder to plug in at home to record what was happening. There was no hassle, after a couple of days I took the recorderback and they said it was because we were a high user and at the end of the line. They came and back fed (that's connected in parallel) as a temporary measure from the end of the road to another sub stations output in the next road. Some days later they severed the original supply about two thirds of the way down the road so the end houses were now all fed from the higher capacity main. No problems since. No interupptions to supply either, all worked on live.
In the lab where I used to work, the mains voltage would rise to 255V after everyone had left for the day. I saw this destroy a switched mode power supply that had been designed in Spain and not adequately tested over the full voltage range.
I once did a gig in a theatre where the mains voltage was 217 and the custom electronics we had built refused to work. I asked the chief electrician about it, and he said he had his own substation and set it to 217 to make the bulbs in the stage lighting last longer. 🙁 He refused to turn it up just for us, so some frantic last-minute mods were in order.
So, I have seen both ends of the 216-253V European range. 🙂
I once did a gig in a theatre where the mains voltage was 217 and the custom electronics we had built refused to work. I asked the chief electrician about it, and he said he had his own substation and set it to 217 to make the bulbs in the stage lighting last longer. 🙁 He refused to turn it up just for us, so some frantic last-minute mods were in order.
So, I have seen both ends of the 216-253V European range. 🙂
Forgot to give an update.
After the first monitoring SP informed me that my supply was within regulation limits.
November 2014:
Scottish Power came back and installed the recording monitor again for another week and also installed on the transformer pole that feeds the 6 houses.
They confirmed this time that my supply is out of spec and will look into it, with a view to solving the problem.
They think it may be down to too many big loads on one phase and I pointed to the two swimming pools that are in houses next door to me.
But, I still have one low voltage phase.
After the first monitoring SP informed me that my supply was within regulation limits.
November 2014:
Scottish Power came back and installed the recording monitor again for another week and also installed on the transformer pole that feeds the 6 houses.
They confirmed this time that my supply is out of spec and will look into it, with a view to solving the problem.
They think it may be down to too many big loads on one phase and I pointed to the two swimming pools that are in houses next door to me.
But, I still have one low voltage phase.
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Andrew
Why did SP do anything at all? Your original voltage was well within the new harmonized 230V +/- 10% acceptable range and also just within the old 240V +/- 6%.
Oops, didn't read your update message.
Why did SP do anything at all? Your original voltage was well within the new harmonized 230V +/- 10% acceptable range and also just within the old 240V +/- 6%.
Oops, didn't read your update message.
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It was out of spec the first time.
That was finally admitted when I got to speak to the person who examined the monitoring evidence.
But somehow a standard letter was sent saying that it was in spec.
During this later discussion Oct/Nov 2014, he realised I still had an issue and he arranged for the second test.
That was finally admitted when I got to speak to the person who examined the monitoring evidence.
But somehow a standard letter was sent saying that it was in spec.
During this later discussion Oct/Nov 2014, he realised I still had an issue and he arranged for the second test.
Very interesting! But that ornery chief electrician had studied the attached bulb life chart and wasn't going to give up FOUR times their potential lifespan just for your noisy gig. Plus he'd had the experience previously of being a nice guy and turning it up for somebody and then blown bulbs during that show...
Attachments
Problem solved.
Scottish Power fitted a bigger 11000:400Vac transformer. Changed from 50kVA to 200kVA
And they rebalanced the 6 houses to get more equal current draw.
As well as the two swimming pools, one of my neighbours has gone from oil heating to all electric and he has a hot tub. That is a big load if both are ON !
I have measured three times since the change over and the biggest difference between the phases was ~3Vac.
I am well happy.
They fitted the monitor for a third time for three days and reported back to say all is in spec now.
Shame it took so long to get to the final solution. But as reported in post1, their initial reaction/action was exemplary.
Scottish Power fitted a bigger 11000:400Vac transformer. Changed from 50kVA to 200kVA
And they rebalanced the 6 houses to get more equal current draw.
As well as the two swimming pools, one of my neighbours has gone from oil heating to all electric and he has a hot tub. That is a big load if both are ON !
I have measured three times since the change over and the biggest difference between the phases was ~3Vac.
I am well happy.
They fitted the monitor for a third time for three days and reported back to say all is in spec now.
Shame it took so long to get to the final solution. But as reported in post1, their initial reaction/action was exemplary.
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Good to know its finally been resolved Andrew. At the end of the day they had no option but to sort it by whatever means needed.
well 2 years problem report to solution not bad for where i come from,and you probably was only one who called them. i may be dumb question, but what exact problem you had?i mean does some of your equipment didnt work or that 12-17V spiking was bothering you?
in croatia , remote vilage it measure from 232V to 242V all that in matter of minute.
in croatia , remote vilage it measure from 232V to 242V all that in matter of minute.
Nothing got damaged and nothing failed to run.
But I was aware that sometimes when I was testing a new assembly that voltage was much lower than previous day.
So I went and measured the three phases to discover there was a problem with low voltage and that the problem varied a lot and between the phases.
But I was aware that sometimes when I was testing a new assembly that voltage was much lower than previous day.
So I went and measured the three phases to discover there was a problem with low voltage and that the problem varied a lot and between the phases.
3phase has been to each of my 3 homes.
The power distribution system in the UK and I think around the world is all 3phase.
The cable running past your home will be 3phase.
For houses they normally tap off one phase and Neutral and the armour and bring that into your distribution board.
My homes just had two extra tappings to give 3phases + Neutral and the armour.
Phase to Neutral is the normal voltage we refer to.
Phase to phase voltage is sqrt(3) times phase to neutral voltage
230Vac phase to neutral is the same as 398.37Vac phase to phase.
That's the voltage the lines men and the chap that installed the monitor are exposed to.
The new transformer on the pole outside my neighbours house will have three outputs at 240Vac (single phase), or 440Vac (3phase) and it has three inputs @ 11kVac (3phase). Those three overhead wires that the linesmen have to work on are at 11kVac. That's what they are exposed to, that's what they think about, that's what they call it.
The power distribution system in the UK and I think around the world is all 3phase.
The cable running past your home will be 3phase.
For houses they normally tap off one phase and Neutral and the armour and bring that into your distribution board.
My homes just had two extra tappings to give 3phases + Neutral and the armour.
Phase to Neutral is the normal voltage we refer to.
Phase to phase voltage is sqrt(3) times phase to neutral voltage
230Vac phase to neutral is the same as 398.37Vac phase to phase.
That's the voltage the lines men and the chap that installed the monitor are exposed to.
The new transformer on the pole outside my neighbours house will have three outputs at 240Vac (single phase), or 440Vac (3phase) and it has three inputs @ 11kVac (3phase). Those three overhead wires that the linesmen have to work on are at 11kVac. That's what they are exposed to, that's what they think about, that's what they call it.
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Glad you got it sorted.
Sounds like your neighbor is quite a power hog! What's your cost per KWH?
In North America most power is distributed in 3 phase. But in domestic (home) service the step down transformer is 2 phase. We get 2 legs of 120V each, or ~240 between them, with the transformer center tap as neutral. We use 1 leg and neutral for most power around the house, but big items like water heaters, air conditioning, cookers, clothes dryers, etc get 240V. (We still call it 220V, but it runs higher now). No way to get 3 phase in most residential areas, the transformers are not set up for it.
Sounds like your neighbor is quite a power hog! What's your cost per KWH?
In North America most power is distributed in 3 phase. But in domestic (home) service the step down transformer is 2 phase. We get 2 legs of 120V each, or ~240 between them, with the transformer center tap as neutral. We use 1 leg and neutral for most power around the house, but big items like water heaters, air conditioning, cookers, clothes dryers, etc get 240V. (We still call it 220V, but it runs higher now). No way to get 3 phase in most residential areas, the transformers are not set up for it.
~11p/kWhr + ~16p/day
no extra for the three phase and no extra for the 3phase meter.
The three phase went in during the house build and that cost no extra either.
no extra for the three phase and no extra for the 3phase meter.
The three phase went in during the house build and that cost no extra either.
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That's nice. 3 phase in residential is rare here.
Here on the island of Hawaii our rates just went down a bit (oil is cheaper). We are at about $0.39/KWH or 24p, in Scottish terms. Solar pays off fast. 😉
Here on the island of Hawaii our rates just went down a bit (oil is cheaper). We are at about $0.39/KWH or 24p, in Scottish terms. Solar pays off fast. 😉
I just got notification that my supplier company 1year contract is coming to an end.
They are putting up my price.
The 16p/day stays the same.
The 11p/kWhr is going up to around 12 to 13p/kWhr
Another Email arrived yesterday to say they are offering a better deal, but will not reveal the better price until 12th Jan.
BTW,
the transmission company is UK nationwide
The distribution company is done on a region by region arrangement and the Transmission company cannot offer this.
The supplier company is different again. These can supply in any region they want to operate. But their prices in each region are different. They are based on the Home Region company's retail rates plus or minus their own discount.
What a weird and complicated system where only one set of wires brings in the same electricity.
They are putting up my price.
The 16p/day stays the same.
The 11p/kWhr is going up to around 12 to 13p/kWhr
Another Email arrived yesterday to say they are offering a better deal, but will not reveal the better price until 12th Jan.
BTW,
the transmission company is UK nationwide
The distribution company is done on a region by region arrangement and the Transmission company cannot offer this.
The supplier company is different again. These can supply in any region they want to operate. But their prices in each region are different. They are based on the Home Region company's retail rates plus or minus their own discount.
What a weird and complicated system where only one set of wires brings in the same electricity.
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