Voltage Levels And Vo

Hi all

Quick question on G83-2 Voltage levels from a VO guy.

Under G83-2 Voltage levels for stage 1 disconnect of inverters are allowed to be up to 262volts, do you feel this will have an impact on surrounding properties on the same connection point, taking into account that house hold appliances are rated nowadays at 220-230 volts under CE marks.

No, I don`t!

Unless a huge number of plants were installed; on the same LV section; the V rise on the grid ven if they were;would be negligable.

Even if they were to have a lot of 4KW installs on a phase; they have +10 / -6 % to play with, before they have to change the tap on the TX

Why would you think it to be a problem?

Canoeboy said:

And whats a VO guy ?

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well from his other post, he is one of those that believes voltage optimization is the best thing since sliced bread, and doesnt understand how flawed it is

Thanks for the responses guys,

Yes I am in favour of Voltage Optimisers but not just on the energy saving side (which it does) but also on the safety side on preventing appliances made for Europe and rated 220-230v and exposed to our all to frequent 250v.

Anyway onto the original point, are you suggesting that PV does not push up the localised grid voltage?

Sorry you are looking at it the wrong way, yes the grid has a fixed resistance applicable to the localised area, when you connect a load onto the line the voltage will naturally drop, now if you inject further current into the line you will raise the grid voltage. Have you ever thought why we are getting an increased amount of inverters cutting out? I am not going to bother responding to your parting comment

matt hunt said:

 I am not going to bother responding to your parting comment

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unfortunately, many of us here are qualified & competent electricians, who fully understand the theory behind how electrics work, and can easily see why 'VO' doesnt work

As am I, I would be interested in hearing your educated opinion on why VO doesn't work?

You have missed the fact that the generating stations work the same way.

Thus if the grid voltage rises then the generating stations will put less power into the grid, thus reducing their voltage rise, thus, this will harmonise the grid voltage.

matt hunt said:

As am I, I would be interested in hearing your educated opinion on why VO doesn't wor

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anything that heats (i.e shower, cooker, iron, kettle) will have a lower voltage, therefore lower input. but the total output needs to be the same. so it may be using less current, but it will take longer to do the job. using the same power, if not more(due to more energy wasted from heat loss whilst it takes longer to heat something)

incandescent lamps will use less electric due to the lower voltage, but it will also be dimmer. so you would actually save electric, but it wouldnt be as bright. other alternative (and cheaper) would simply be using a lower rated lamp. or use VO and stick a higher rated lamp in to get it brighter again.

switch mode power supplies will use more current at a lower voltage to maintain the output

Then we will have to agree to disagree, as the grid voltage will rise with a fixed impedance, also the voltage will drop on the other 2 phases in the street if they are imbalanced, and their impedance is also fixed!

matt hunt said:

Then we will have to agree to disagree, as the grid voltage will rise with a fixed impedance, also the voltage will drop on the other 2 phases in the street if they are imbalanced, and their impedance is also fixed!

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can i ask, what electrical qualifications do you have? are you a qualified electrician?

matt,

The grid will take all of the current that you can throw at it.

It will soak it up and it will just disappear.

All of the "NG" generating stations on the grid are closed loop.

Microgeneration is open loop, so the micro generators will power the grid in preference to the power stations.

Thus as the micro generation feeds into the local grid the requirement from the EHV grid etc. will drop, thus the power stations will reduce their output, as I say they are closed loop.

Thus there will not be a grid voltage rise due to microgeneration, unless it has not been installed correctly, and been notified correctly to the local DNO.

Andy, the total output needs to be closer to what it is designed to run at, you say that a light is dimmer with lower voltage but also a light is brighter with higher voltage, your argument on getting a lower powered light is a bit topsey turvey. If you buy a 60 watt light then why would you want it to consume nearer 70 watts at a higher voltage??

Gees guys I am not getting enough breathing space to go and get another tinny  

OK got one Guinness

Canoeboy I just asked you a question in another forum which is probably in the wrong place, I thought G83-2 settings are also 262v

Why are they set at 262,2v, surely this is potentially detrimental to CENELEC limits, this is a question not a statement

Seems to go against everything we been debating about over the last couple of hours, BTW the ENA released a report on increased voltage levels due to PV installs and recommends inline voltage regulators as one of the solutions :Blushing

Sorry  - got to pile in..

Did you know that the water level in the north sea rose today, cos I took a leak in it :slap

Yes, its daft  - but the theory is the same as you are proposing - a drop of pee in a few million billion gallons of water is akin to a 3680W inverter affecting the ( at this very moment) 23.85GW of demand.

And V-phase - VO - can I just say this:

"Energy cannot be created or destroyed. All we can do is change its state."

Its a sales pitch for suckers.

Like the lottery - a tax on people who are (very) bad at maths. :slap

This is a paper from the ENA to the DNOs, and I quote " localised penetration of micro-generation may give rise to localised voltages exceeding statutory limits and even operation of G83 protection. The ability to monitor voltage profiles and even utilise this information for active voltage control on LV Networks where necessary is therefore an essential requirement" He shoots he scores

What you starting to believe me that maybe, just maybe micro-generation may increase local grid voltages??