Are Over Voltage Problems widespread

[matthunt]

Are any of you seeing High voltage problems in houses with Solar/PV installed in same street?

I attended a call out a few weeks ago due to the fuse board apparently smoking. When i arrived it transpired it was the shower circuit, the voltage measured was 246v and the current 36 amps meaning a 7.5kw shower drawing 8.8kw through a cartridge type Wylex db. The fuse was rated at 30amps and you just could not touch it due to the heat. We all know of the inherant problems with this type of fuse whilst continuing to operate on steady over current. Has anyone else seen this type of problem? as i am aware that multiple PV installs in a street on the same phase will obviously boost the voltage due to the nature of the invertors.

 

[Knobhead]

nope, checked all connections,it was purely an overvoltage problem, just wanted to know if anyone else had come across this before?

I doubt any one has, because it’s a none problem other than in your mind.

Now listen to the people that know what they are talking about and look for a real fault.

You could disconnect the PV input, but I don’t think your clients will be to impressed.

 

[matthunt]

As a matter of interest has anyone read John Whittakers guide to the 17th Edition? specifically in answer to Tonys post.

 

[Engineer54]

As a matter of interest has anyone read John Whittakers guide to the 17th Edition? specifically in answer to Tonys post.

So what has been written in this guide on this then??

 

[GLENNSPARK]

this boy is goin on about a percieved `overvoltage`....not with the figures he gave in the first place ....further more he needs to consider that voltage (and so current) is a bit like the sea....with sags n swells.....
as some others have posted here....its an installation fault.....
check all terminations on this circuit
check all accessories served
check cable CSA + length of run + install method before altering OPD....

 

[matthunt]

Sorry it is John Whitfield not John Whittaker, thankyou for your commets Glennspark, i do know the relationship between voltage and current and i am not 'a boy' but thankyou for your perception on me being younger than what i actually am. Read page 1 and 2 of the guide and make your own mind up.

 

[MDJ]

Not June whitfield?

 

[matthunt]

No not June nor Terry

 

[Engineer54]

Sorry it is John Whitfield not John Whittaker, thankyou for your commets Glennspark, i do know the relationship between voltage and current and i am not 'a boy' but thankyou for your perception on me being younger than what i actually am. Read page 1 and 2 of the guide and make your own mind up.

Still waiting to find out what this John Whitfield guide to the 17th Ed had to say?? lol!!

 

[matthunt]

Quote "Tables in the 17th Edition have, for the first time, been recalculated to take account of the unified voltage levels. Following this lead, calculatons in this book have been based on supply voltages of 230v and 400v, but the electrician must bear in mind that TRUE VALUES are much higher"

 

[matthunt]

In other words guys , the 17th Edition Regs calculatons/values are based on European voltages and dont take into account our +-10% as defined by CENELEC

 

[GLENNSPARK]

well i always had ours as 253V-216V...
or =10% -6%....

- - - Updated - - -

 

[matthunt]

That was changed in 2008 Glennsparko +/-10%

 

[Knobhead]

Quote "Tables in the 17th Edition have, for the first time, been recalculated to take account of the unified voltage levels. Following this lead, calculatons in this book have been based on supply voltages of 230v and 400v, but the electrician must bear in mind that TRUE VALUES are much higher"

It’s about time the regulations were recalculated to reality. Will you get it through to your brain cell. The DNO’s don’t give a ---- about the IET’s inane pontificating.
You get whatever they give you.

 

[oldtimer]

yep we pretend our voltage is 230-400 but in reality it is 245-415 just because we say we have parity does not mean we do have it plus if you measure say 245 during the day you can bet your life it will rise at night when the load drops off hence why some burglar alarms and other electronic appliances failing at night

 

[matthunt]

253-207v and 440-360v nowadays, anyway thats not important to this thread, the thing that surprises me is the lack of undertanding of voltages and the effect on equipment it potenially has with Electricians in the UK