KME, we agree on something at least, the v-phase product was not very good, there are a lot better whole house solutions available on the market today, but unfortunately the rest of your statement is silly, the over-voltage issue is something us householders and engineers will be dealing with for years to come, but very importantly not on an energy saving measure but on a safety measure.
Voltage Levels And Vo
- Thread starter matt hunt
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Now:
Which of the "over-voltage issues" are we referring to?
The theoretical one, caused by the European "harmonisation" ( :slap ) - i.e call it something it isn`t.
or
The physical one, which has existed for a long time, caused by the DNO`s lengths of LV, whch means that they have to lift the voltage ( within limits that have shrunk since the harmonisation) on the sub taps, in order to comply with the minimum voltage levels on the ends of the runs.
or
The semi-existential one; which can may artificially increase the LV on the end of a leg, under certain conditions; exacerbated by the propensity of SSEGs to all create at the same time, and all stop at the same time ( within a given geographic).
I still have equipment in my house ( admittedly primarily test equip. and audio), which are provided with taps for200, 220, 240, and 250 V
The equip in question is, in the main, valve stuff - Which means this was considered an issue then - long before PV - their solution was to allow the item to be tapped to the right voltage.
You said, a while back, about this being a "safety issue"?
Do you honestly expect me to believe that this is suddenly becoming dangerous, and needs to be addressed by having a "box of tricks" in the circuit?
Using the same rhetoric, can we put 5WW in a box, as they`re even more dangerous ( and there IS proof to back that up!)? :needdrink:
Which of the "over-voltage issues" are we referring to?
The theoretical one, caused by the European "harmonisation" ( :slap ) - i.e call it something it isn`t.
or
The physical one, which has existed for a long time, caused by the DNO`s lengths of LV, whch means that they have to lift the voltage ( within limits that have shrunk since the harmonisation) on the sub taps, in order to comply with the minimum voltage levels on the ends of the runs.
or
The semi-existential one; which can may artificially increase the LV on the end of a leg, under certain conditions; exacerbated by the propensity of SSEGs to all create at the same time, and all stop at the same time ( within a given geographic).
I still have equipment in my house ( admittedly primarily test equip. and audio), which are provided with taps for200, 220, 240, and 250 V
The equip in question is, in the main, valve stuff - Which means this was considered an issue then - long before PV - their solution was to allow the item to be tapped to the right voltage.
You said, a while back, about this being a "safety issue"?
Do you honestly expect me to believe that this is suddenly becoming dangerous, and needs to be addressed by having a "box of tricks" in the circuit?
Using the same rhetoric, can we put 5WW in a box, as they`re even more dangerous ( and there IS proof to back that up!)? :needdrink:
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Jono Pashley
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Actually KME its a little bit of all of them put together, we realise (as hopefully by now others may on the forum) that the DNOs keep the voltage on the high side for voltage drop and additional revenue..
Additionally our localised network lines have a fixed resistance, when a load is placed across the lines the voltage drops, if we are generating and pushing current into the grid at this time then the voltage rises, yes this is tied to a geographic area and within the same vicinity multiple systems will all contribute to raise the voltage.
The ENA are clearly aware of this issue and they have made the DNOs aware of it, the white paper from the ENA was written in 2010 in preparation for the smart meter rollout, (as we all know the mass rollout has still not yet occurred)
The paper is titled ENA requirement for electricity smart meters v2 220410.pdf
Additionally our localised network lines have a fixed resistance, when a load is placed across the lines the voltage drops, if we are generating and pushing current into the grid at this time then the voltage rises, yes this is tied to a geographic area and within the same vicinity multiple systems will all contribute to raise the voltage.
The ENA are clearly aware of this issue and they have made the DNOs aware of it, the white paper from the ENA was written in 2010 in preparation for the smart meter rollout, (as we all know the mass rollout has still not yet occurred)
The paper is titled ENA requirement for electricity smart meters v2 220410.pdf
2 thing Matt,
1/ G83 inverters don't output 263 V, they are designed to run slightly higher than grid voltage, and upto the 260V mark before they trip out. as the top value for the grid i in theory around 251V the most a G83 inveretr will output for any time is around 253V. Most are actually set for around 253V tops, but on some makes this can be set higher to allow for grid issues, something I've had to do once in 3 years.
2/ have a look at my post from which? magazine - not very complimentary about about VO units. I attanded a sales talk about VO some time ago, and when he plugged his demo board in, the lights fitted dimmed slightly.
You also see a lot of crap about VO units helping soalr PV be more efficient, but as the PV has to be connected to the household supply before the VO (cos they can't handle working backwards) I am very confused as to how this could actually work.
Getting back to the grid, my local DO friend did mention that they have been having problems with the 11kV network in areas with high PV concentration, particularly when they get a social housing group install PV on every house in an estate without contacting them first. But as paddler says, this is probably more to do with ancient equipment than the PV itself, as their trannies can only handle a 25% back-feed
1/ G83 inverters don't output 263 V, they are designed to run slightly higher than grid voltage, and upto the 260V mark before they trip out. as the top value for the grid i in theory around 251V the most a G83 inveretr will output for any time is around 253V. Most are actually set for around 253V tops, but on some makes this can be set higher to allow for grid issues, something I've had to do once in 3 years.
2/ have a look at my post from which? magazine - not very complimentary about about VO units. I attanded a sales talk about VO some time ago, and when he plugged his demo board in, the lights fitted dimmed slightly.
You also see a lot of crap about VO units helping soalr PV be more efficient, but as the PV has to be connected to the household supply before the VO (cos they can't handle working backwards) I am very confused as to how this could actually work.
Getting back to the grid, my local DO friend did mention that they have been having problems with the 11kV network in areas with high PV concentration, particularly when they get a social housing group install PV on every house in an estate without contacting them first. But as paddler says, this is probably more to do with ancient equipment than the PV itself, as their trannies can only handle a 25% back-feed
Hi Canoeboy, it was you that mentioned the ENA, all I did was gave you the facts from them. Smart metering is there for measuring not only peoples bills remotely but also their voltage levels and also reactive power etc, (don't worry guys I am totally aware we are not charged for this domestically at present)
I don't know who plumber is in any way shape or form.
I don't know who plumber is in any way shape or form.
Hi Binky
Please take into account I am not a PV Engineer but a power Engineer,
1, I tested an inverter that had arrived into the Country 3 weeks ago labelled G83-2 and it was set at 262v, I can only presume Manufacturers would set them at 253 to comply with G59 and G83-2,would this seem right with you guys?
2. 'Which Magazine' should stick to dodgy Chinese white goods as they know nothing about power, indeed I took them to task over labelling a PFC plug in unit as a voltage optimiser, their reply was that their readers would understand this easier, even though it could potentially bring an industry into disrepute
Of course the lights would dim slightly as they were running too bright in the first place and as such were consuming more power than they are designed to.
I am very interested in your comment that a VO unit cannot work backwards, is this comment from a regulatory point of view or an electrical point of view?
Now onto VO working alongside PV, lets say you are generating 3kw at a specific time which maybe utilised in an immersun unit for a 3kw 230v immersion element into a house for example, the grid voltage is 245volts, will you be able to heat the water FOC or will it cost you money??
Onto your last paragraph, I am in total agreement our network is ancient and practically on its knees, clearly the DNOs will not be replacing all of this within the UK in the foreseeable future, so we have to engineer our way through the solutions as we meet the problems.
I am in total favour of PV and renewables but unless we find and work through solutions to get rid of the by-product (excess voltage) then the market will be slower for you guys within this industry.
Please take into account I am not a PV Engineer but a power Engineer,
1, I tested an inverter that had arrived into the Country 3 weeks ago labelled G83-2 and it was set at 262v, I can only presume Manufacturers would set them at 253 to comply with G59 and G83-2,would this seem right with you guys?
2. 'Which Magazine' should stick to dodgy Chinese white goods as they know nothing about power, indeed I took them to task over labelling a PFC plug in unit as a voltage optimiser, their reply was that their readers would understand this easier, even though it could potentially bring an industry into disrepute
Of course the lights would dim slightly as they were running too bright in the first place and as such were consuming more power than they are designed to.
I am very interested in your comment that a VO unit cannot work backwards, is this comment from a regulatory point of view or an electrical point of view?
Now onto VO working alongside PV, lets say you are generating 3kw at a specific time which maybe utilised in an immersun unit for a 3kw 230v immersion element into a house for example, the grid voltage is 245volts, will you be able to heat the water FOC or will it cost you money??
Onto your last paragraph, I am in total agreement our network is ancient and practically on its knees, clearly the DNOs will not be replacing all of this within the UK in the foreseeable future, so we have to engineer our way through the solutions as we meet the problems.
I am in total favour of PV and renewables but unless we find and work through solutions to get rid of the by-product (excess voltage) then the market will be slower for you guys within this industry.
the VO industry is already in disrepute,
its all snake oil,
simple basics tells us
power in = power out
ye cannae change the laws of physics
its all snake oil,
simple basics tells us
power in = power out
ye cannae change the laws of physics
is it like a boiler engineer?
a made up name that is NOT really an engineer?
my real job is a beer engineer
a made up name that is NOT really an engineer?
my real job is a beer engineer
Its requesting an opinion to engage intelligent conversation, as a whole it has been I think!
My role in life after getting bored with Electrical Installations was to develop Voltage Optimisation Technologies (no surprise there to you)
What I am trying to do is introduce a realisation that VO and PV are complimentary and can actually be a revenue source for PV Installers
My role in life after getting bored with Electrical Installations was to develop Voltage Optimisation Technologies (no surprise there to you)
What I am trying to do is introduce a realisation that VO and PV are complimentary and can actually be a revenue source for PV Installers
263V MAX, not permanently at this voltage unless its some cheap Chinese crap. They are called grid-tied becuase they monitor the grid and output a few volts higher, so like water at slightly higher level, it flows first so energy fron the array can be used before energy from the grid. If the grid was at 220V they will output something like 222V
The inverters don't just push volts back into the system, they output amps as well, up to 16A max to be compliant with DNO requirements. The ampage being the actual limitation, not voltage or 4kW, hence you see a lot of inverters listed as 3.68kw 16A limited..
With the VO units. in theory its just a transformer and should work in reverse, but I've never found a VO unit that states they can be back fed from solar, which suggests it's not possible, or doesn't work.
ahh so this is one big sales pitch then LOL. Immersuns sell well, VO is a possible if it saves inverters from voltage spikes such as during lightning strikes.
as a complimentary pitch for PV, I've never been convinced, so get technical and prove us wrong . Could get messy :slapopcorn
The inverters don't just push volts back into the system, they output amps as well, up to 16A max to be compliant with DNO requirements. The ampage being the actual limitation, not voltage or 4kW, hence you see a lot of inverters listed as 3.68kw 16A limited..
With the VO units. in theory its just a transformer and should work in reverse, but I've never found a VO unit that states they can be back fed from solar, which suggests it's not possible, or doesn't work.
ahh so this is one big sales pitch then LOL. Immersuns sell well, VO is a possible if it saves inverters from voltage spikes such as during lightning strikes.
as a complimentary pitch for PV, I've never been convinced, so get technical and prove us wrong . Could get messy :slap
opcorn Hi Binky, of course they can if they are auto-transformer configured. if you subtract say 15v to the inverter then pushing current back through the transformer in the opposite direction will increase by the same amount, there is a slight problem in doing this though within regulations!
Hi Canoe, I have over 4000 systems installed in the UK to date so we have plenty of case studies in single and 3 phase systems, as I mentioned a while ago it is not just about the energy savings of typically 8%, its about the safety of the European equipment that we use in our houses, trust me a product made for Europe at 220-230v does not like 250v up it, if you don't believe me call that "popular mobile phone manufacturers" Technical department and ask what voltage their chargers are rated at!
You know the old saying 'they don't make them like they used to' well this is actually spot on, we had an old hoover vacuum cleaner that was rated at 240v-250v that was still running when we scrapped it after 10 years, how long do modern day vacuum cleaners last, we are on our 3rd in 5 years!!
You know the old saying 'they don't make them like they used to' well this is actually spot on, we had an old hoover vacuum cleaner that was rated at 240v-250v that was still running when we scrapped it after 10 years, how long do modern day vacuum cleaners last, we are on our 3rd in 5 years!!
oh, blue bass , havent seen that in ages, only get red round here, :|
canoey, can you renew my MEWPs for me? :C
canoey, can you renew my MEWPs for me? :C
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