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Hi guys so finally back form my holiday and the power logger was here.
Have been monitiorng it and it is reporting 235V...only fluctuates about =/- .2 either way. I know it will be most intersting to read it when the issue occurs next but thought this would be good info now as I dont think I will see the error until next summer due the weather and sun is now lower in the sky. (ony happens on sunny days in summer May-August)
Also managed to get the BS standard from the cable exiting the Inverter to the consumer unit is it BS EN 50525-5-11 300/500V. Is that Ok for a 15 mtr run carrying exported excess power thorugh my attic in 27-30 degress of heat?
Also having my electrician check the size of the cable running from my junction box to my consumer unit in case it is under spec'd ref the below thread i noted on an irish board, I want to know if I have 25mm sq cable or not.
Voltage drop in house - what to expect - https://www.boards.ie/vbulletin/showthread.php?t=2057837652 .
Have been monitiorng it and it is reporting 235V...only fluctuates about =/- .2 either way. I know it will be most intersting to read it when the issue occurs next but thought this would be good info now as I dont think I will see the error until next summer due the weather and sun is now lower in the sky. (ony happens on sunny days in summer May-August)
Also managed to get the BS standard from the cable exiting the Inverter to the consumer unit is it BS EN 50525-5-11 300/500V. Is that Ok for a 15 mtr run carrying exported excess power thorugh my attic in 27-30 degress of heat?
Also having my electrician check the size of the cable running from my junction box to my consumer unit in case it is under spec'd ref the below thread i noted on an irish board, I want to know if I have 25mm sq cable or not.
Voltage drop in house - what to expect - https://www.boards.ie/vbulletin/showthread.php?t=2057837652 .
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RonanIrl: Good morning. In the meantime you could check what I mentioned in #15 and ask the electrician to check the tightness and correctness of all the ac power connections between the inverter and the intake including where any mcbs/rcbos/rcds for the pv system are connected to busbars.
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I am still thinking about your problem which I believe to be due to voltage rise of the network caused by other micro generation schemes (on very sunny days when export is high) near you on the distribution circuit you share with them, or volt drop along the cables between your inverter and the network, or a bit of both. Wilko and I have done some voltage drop estimates which we will come to later.
Meanwhile, to inform our analysis:
1. Is your home and those in the vicinity supplied by overhead or underground cables?
2. Can you see the transformer? If yes could you take a picture of it please?
3. Are you among those nearer to the transformer or those further away?
4. How many other pv schemes are in your immediate vicinity and what is their installed power - assume 250W a panel - so a four panel array would be 1kW.
5.Might you measure or re-check your estimate of the length of the 6mm2 cable from the inverter to the mains supply intake and re-consider how much of its length is in the loft (which is hot in summer).
6. If the supply is overhead - the classical 4 cables strung between poles - could you look carefully to see to which of the three upper cables is connected any local pv generation scheme. I wonder if by happenstance you are all or most of you are on the same phase cable - there are three phase cables and the lower one is the neutral.
7. A nudge again about answering my questions in #15.
8. I assume you are now taking some readings of home voltage during peak sun (ie midday) to discover any trends.
Meanwhile, to inform our analysis:
1. Is your home and those in the vicinity supplied by overhead or underground cables?
2. Can you see the transformer? If yes could you take a picture of it please?
3. Are you among those nearer to the transformer or those further away?
4. How many other pv schemes are in your immediate vicinity and what is their installed power - assume 250W a panel - so a four panel array would be 1kW.
5.Might you measure or re-check your estimate of the length of the 6mm2 cable from the inverter to the mains supply intake and re-consider how much of its length is in the loft (which is hot in summer).
6. If the supply is overhead - the classical 4 cables strung between poles - could you look carefully to see to which of the three upper cables is connected any local pv generation scheme. I wonder if by happenstance you are all or most of you are on the same phase cable - there are three phase cables and the lower one is the neutral.
7. A nudge again about answering my questions in #15.
8. I assume you are now taking some readings of home voltage during peak sun (ie midday) to discover any trends.
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Marconi thanks.
See my comments below.
Voltage meter is in place has hadly fluctuated since install more or less stable bwteen 235-238Volts. Jumped to 238 when the run was out one day.
Today my installer said he is coming on friday next to replace the shunt as it may be faulty and cutting off above 70 degrees. Guess that could be the issue.
I am still thinking about your problem which I believe to be due to voltage rise of the network caused by other micro generation schemes (on very sunny days when export is high) near you on the distribution circuit you share with them, or volt drop along the cables between your inverter and the network, or a bit of both. Wilko and I have done some voltage drop estimates which we will come to later.
Meanwhile, to inform our analysis:
1. Is your home and those in the vicinity supplied by overhead or underground cables?
Underground cable from a mini box in an estate of only 5 houses.
2. Can you see the transformer? If yes could you take a picture of it please?
I can see the mini box not sure if it the trnsformer but its juts a steel box approx 100x100x50 cm with caustion high voltage sticker on it
3. Are you among those nearer to the transformer or those further away?
The box is only 7 meters from meters from my supply meter box on my wall.
4. How many other pv schemes are in your immediate vicinity and what is their installed power - assume 250W a panel - so a four panel array would be 1kW.
There is 4 houses just around the corner with 5 panels each for powering heat pumps etc (Irish build laws now require them on all new build houses to meet A rating) They were just built last summer and are now occupied. The direction they face is the same as my own roof. So 20 panels in total and they look like 250 panles where as mine are 350 panels.
5.Might you measure or re-check your estimate of the length of the 6mm2 cable from the inverter to the mains supply intake and re-consider how much of its length is in the loft (which is hot in summer). Its definitely 14-15 M in length measured form inverter to consumer unit last week and about 9 Meters run in the attic (remainder is drops up and down thruogh cavitys) where it get to approx 27 in summer.
6. If the supply is overhead - the classical 4 cables strung between poles - could you look carefully to see to which of the three upper cables is connected any local pv generation scheme. I wonder if by happenstance you are all or most of you are on the same phase cable - there are three phase cables and the lower one is the neutral.
Everything is underground in the estate it only runs overhead outside and its spagetti junction where it braches off unfortuantely impossible to follow a single line.
7. A nudge again about answering my questions in #15.
While the setting seems wrong i can 100% confirm that power is exporting when the Battery is full and the house is not drawing all the genertaed power. Im reluctant to change this setting but will ask the engineer next friday friday.
8. I assume you are now taking some readings of home voltage during peak sun (ie midday) to discover any trends.
As above see top off comments.
[/QUOTE]
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Tends to only happen on super sunny summer days, doesnt happen at all in winter guess sun angle is also a factor here so it must be related to maxuimum generataion sustained from the panels causing the issue. I have 1.5 years of dongle data and it only happned in May - August 2020 on the sunniest warm days (system wsa only installed late August 2019 so missed summer 2019). Dont think it will happen agian until next summer when sun is at its optimum angle which seesm to be above 45 degrees which is interestng as the panels are at 45 degress on my roof (Pefect Perpendicular angle to the sun on the days it happens as i have a sun tracker app on my phone and the tiem of cut off is just as the sun goes aove 45 and sky is clear and weather very warm). Maybe it is this shunt they are coming to replace overheating.
See my comments below.
Voltage meter is in place has hadly fluctuated since install more or less stable bwteen 235-238Volts. Jumped to 238 when the run was out one day.
Today my installer said he is coming on friday next to replace the shunt as it may be faulty and cutting off above 70 degrees. Guess that could be the issue.
I am still thinking about your problem which I believe to be due to voltage rise of the network caused by other micro generation schemes (on very sunny days when export is high) near you on the distribution circuit you share with them, or volt drop along the cables between your inverter and the network, or a bit of both. Wilko and I have done some voltage drop estimates which we will come to later.
Meanwhile, to inform our analysis:
1. Is your home and those in the vicinity supplied by overhead or underground cables?
Underground cable from a mini box in an estate of only 5 houses.
2. Can you see the transformer? If yes could you take a picture of it please?
I can see the mini box not sure if it the trnsformer but its juts a steel box approx 100x100x50 cm with caustion high voltage sticker on it
3. Are you among those nearer to the transformer or those further away?
The box is only 7 meters from meters from my supply meter box on my wall.
4. How many other pv schemes are in your immediate vicinity and what is their installed power - assume 250W a panel - so a four panel array would be 1kW.
There is 4 houses just around the corner with 5 panels each for powering heat pumps etc (Irish build laws now require them on all new build houses to meet A rating) They were just built last summer and are now occupied. The direction they face is the same as my own roof. So 20 panels in total and they look like 250 panles where as mine are 350 panels.
5.Might you measure or re-check your estimate of the length of the 6mm2 cable from the inverter to the mains supply intake and re-consider how much of its length is in the loft (which is hot in summer). Its definitely 14-15 M in length measured form inverter to consumer unit last week and about 9 Meters run in the attic (remainder is drops up and down thruogh cavitys) where it get to approx 27 in summer.
6. If the supply is overhead - the classical 4 cables strung between poles - could you look carefully to see to which of the three upper cables is connected any local pv generation scheme. I wonder if by happenstance you are all or most of you are on the same phase cable - there are three phase cables and the lower one is the neutral.
Everything is underground in the estate it only runs overhead outside and its spagetti junction where it braches off unfortuantely impossible to follow a single line.
7. A nudge again about answering my questions in #15.
While the setting seems wrong i can 100% confirm that power is exporting when the Battery is full and the house is not drawing all the genertaed power. Im reluctant to change this setting but will ask the engineer next friday friday.
8. I assume you are now taking some readings of home voltage during peak sun (ie midday) to discover any trends.
As above see top off comments.
[/QUOTE]
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Tends to only happen on super sunny summer days, doesnt happen at all in winter guess sun angle is also a factor here so it must be related to maxuimum generataion sustained from the panels causing the issue. I have 1.5 years of dongle data and it only happned in May - August 2020 on the sunniest warm days (system wsa only installed late August 2019 so missed summer 2019). Dont think it will happen agian until next summer when sun is at its optimum angle which seesm to be above 45 degrees which is interestng as the panels are at 45 degress on my roof (Pefect Perpendicular angle to the sun on the days it happens as i have a sun tracker app on my phone and the tiem of cut off is just as the sun goes aove 45 and sky is clear and weather very warm). Maybe it is this shunt they are coming to replace overheating.
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- 4,325
The voltage drop Wilko and I estimated for the connection between your inverter and the main intake was between 2(me) to 3(Wilko) Volts at 21 Amps when you export 5kW. Wilko cleverly included the drops across isolators, mcb and at connections which explains his higher figure. As you are so close to the transformer I reckon any volt drop along the cabling between your home and it is of the order 0.5-1V (20 A x 0.05 Ohms = 1V).
In sum between your inverter ac output installation and the transformer a worse case volt rise of circa (nb 3 + 1 =4V) of 235 + 4 = 239V. Not troublesome if your supply voltage is circa 235V since the disconnect figures are typically 255V rolling 10 minutes (IIRC) time averaged, 260V peak for 1 sec and 261 peak immediate - and 239V < 255V.
What we don't yet know is the effect the other solar pv systems at peak sun have on elevating your incoming mains voltage so be be very interesting to find out.
I turned up this article which you might find interesting which helps to explain our line of thinking on your peak sun disconnect problem. For example you will read about the cable between the inverter and the mains intake and the suggestion to double up on it if the run is long - hence our volt drop estimates - to see if this might make a difference. It also explains inverter cycling at high voltage rise. Wilko and I don't understand why there is no fault code reported by your inverter which tends to indicate this is not happening in you case unless the internal logic is that this is not a fault per se but rather an event - I recognise this is semantic thinking. Let us hope for some sunny days next week.
Solar Voltage Rise - why you should care | MC Electrical - https://www.mcelectrical.com.au/solar-voltage-rise-explained/
In sum between your inverter ac output installation and the transformer a worse case volt rise of circa (nb 3 + 1 =4V) of 235 + 4 = 239V. Not troublesome if your supply voltage is circa 235V since the disconnect figures are typically 255V rolling 10 minutes (IIRC) time averaged, 260V peak for 1 sec and 261 peak immediate - and 239V < 255V.
What we don't yet know is the effect the other solar pv systems at peak sun have on elevating your incoming mains voltage so be be very interesting to find out.
I turned up this article which you might find interesting which helps to explain our line of thinking on your peak sun disconnect problem. For example you will read about the cable between the inverter and the mains intake and the suggestion to double up on it if the run is long - hence our volt drop estimates - to see if this might make a difference. It also explains inverter cycling at high voltage rise. Wilko and I don't understand why there is no fault code reported by your inverter which tends to indicate this is not happening in you case unless the internal logic is that this is not a fault per se but rather an event - I recognise this is semantic thinking. Let us hope for some sunny days next week.
Solar Voltage Rise - why you should care | MC Electrical - https://www.mcelectrical.com.au/solar-voltage-rise-explained/
sorry they are 315W Q peak duo black G5 panels
very interesting article I did note a slight voltage increase on the grid last week on a sunny day it was up at 238-240 (normally 235 stable) but the location of other solar installations nearby are minimal as noted above. When the engineer is here next week I’m going to ask him to also check the size of the cables from consumer unit to meter and meter to transformer if possible and let you know the size and length.
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In #1 you said you had 315W panels yet above you wrote 350W - could you confirm which one please?
Also could you give me the details of a panel too so I can look up its specification please?
very interesting article I did note a slight voltage increase on the grid last week on a sunny day it was up at 238-240 (normally 235 stable) but the location of other solar installations nearby are minimal as noted above. When the engineer is here next week I’m going to ask him to also check the size of the cables from consumer unit to meter and meter to transformer if possible and let you know the size and length.
The voltage drop Wilko and I estimated for the connection between your inverter and the main intake was between 2(me) to 3(Wilko) Volts at 21 Amps when you export 5kW. Wilko cleverly included the drops across isolators, mcb and at connections which explains his higher figure. As you are so close to the transformer I reckon any volt drop along the cabling between your home and it is of the order 0.5-1V (20 A x 0.05 Ohms = 1V).
In sum between your inverter ac output installation and the transformer a worse case volt rise of circa (nb 3 + 1 =4V) of 235 + 4 = 239V. Not troublesome if your supply voltage is circa 235V since the disconnect figures are typically 255V rolling 10 minutes (IIRC) time averaged, 260V peak for 1 sec and 261 peak immediate - and 239V < 255V.
What we don't yet know is the effect the other solar pv systems at peak sun have on elevating your incoming mains voltage so be be very interesting to find out.
I turned up this article which you might find interesting which helps to explain our line of thinking on your peak sun disconnect problem. For example you will read about the cable between the inverter and the mains intake and the suggestion to double up on it if the run is long - hence our volt drop estimates - to see if this might make a difference. It also explains inverter cycling at high voltage rise. Wilko and I don't understand why there is no fault code reported by your inverter which tends to indicate this is not happening in you case unless the internal logic is that this is not a fault per se but rather an event - I recognise this is semantic thinking. Let us hope for some sunny days next week.
Solar Voltage Rise - why you should care | MC Electrical - https://www.mcelectrical.com.au/solar-voltage-rise-explained/
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looking back at the last time this happened see the voltage RUA (not sure what this is though) seems it’s lower than the input voltage I get of approx 235v perhaps the issue is here.
03_Rev02_NA.pdf[/URL]
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very interesting article I did note a slight voltage increase on the grid last week on a sunny day it was up at 238-240 (normally 235 stable) but the location of other solar installations nearby are minimal as noted above. When the engineer is here next week I’m going to ask him to also check the size of the cables from consumer unit to meter and meter to transformer if possible and let you know the size and length.
[/QUOTE]
[automerge]1599945719[/automerge]
very interesting article I did note a slight voltage increase on the grid last week on a sunny day it was up at 238-240 (normally 235 stable) but the location of other solar installations nearby are minimal as noted above. When the engineer is here next week I’m going to ask him to also check the size of the cables from consumer unit to meter and meter to transformer if possible and let you know the size and length.
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- Reaction score
- 4,325
Thank you. I will ponder more on the plots. R,S,T or U,V,W or A,B,C identify which phase the voltage refers to. In your case the inverter and your home is single phase which means only voltage for one phase, phase one or R,U,A is measured. I don't think for now solar voltage rise is the problem.
The dc voltage plot clearly shows (but see my PM to you) the voltage dropping from 200 odd volts to near zero volts - this could happen if the shunt relay opens. The dc voltage plot also looks erratic but that may be the time scale selected for the plot. For the shunt relay to remain closed it requires ac power to be available on the supply side of the left hand lockable ac isolator shown in the schematic of your installation in #11. You could ask the electrician who visits on Friday to check thoroughly all the ac connections between the inverter ac output right back to and including where it connects to the incoming mains in case there is an intermittent open circuit perhaps caused by poor contact or a deteriorated contact and similarly between the shunt relay and the ac isolator - which is/are only apparent when high ac currents are flowing eg: high export/backflow power. While he is present he should also check the dc connections to the array and battery.
Could you also look at section 5.5.10 on EPM settings (Electronic Power Management) and tell what settings have been selected:
https://static.solartricity.ie/wp-content/uploads/2018/04/Solis-Hybrid-Inverter-Manual.pdf
I want to establish what priorities have been selected for the use of pv power, battery power, export/backflow power.
The dc voltage plot clearly shows (but see my PM to you) the voltage dropping from 200 odd volts to near zero volts - this could happen if the shunt relay opens. The dc voltage plot also looks erratic but that may be the time scale selected for the plot. For the shunt relay to remain closed it requires ac power to be available on the supply side of the left hand lockable ac isolator shown in the schematic of your installation in #11. You could ask the electrician who visits on Friday to check thoroughly all the ac connections between the inverter ac output right back to and including where it connects to the incoming mains in case there is an intermittent open circuit perhaps caused by poor contact or a deteriorated contact and similarly between the shunt relay and the ac isolator - which is/are only apparent when high ac currents are flowing eg: high export/backflow power. While he is present he should also check the dc connections to the array and battery.
Could you also look at section 5.5.10 on EPM settings (Electronic Power Management) and tell what settings have been selected:
https://static.solartricity.ie/wp-content/uploads/2018/04/Solis-Hybrid-Inverter-Manual.pdf
I want to establish what priorities have been selected for the use of pv power, battery power, export/backflow power.
- Reaction score
- 4,325
RonanIrl: Thank you for the access to your solar PV system which I am studying. Could you confirm a couple of things for me please?
1. You have a generation meter in the ac line from the inverter to the mains intake which does indeed clock up kWh?
2. Do you have a 'current clamp' attached around one of the electricity supplier's meter cables? It will look something like this:
Learn | OpenEnergyMonitor - https://learn.openenergymonitor.org/electricity-monitoring/ct-sensors/installation
It will be hard-wired back to the inverter or connected via a radio signal eg: Wifi.
3. On your electricity bill is the debit amount of electrical energy you have to pay for the difference between your electricity supplier meter reading and your pv generation meter reading?
4. On your bill is their a separate credit for surplus energy you have exported to the grid at a different rate to the units in para 3 - I wager there is not.
Its appears to me that your pv system is set up to optimise 'self-consumption' of solar energy in real-time and if that cannot be achieved ie: your home's load is lower in kW than that being produced at the time by the panels to then store the excess in the battery for use at other times.
Because your backflow(ie: net )export power setting has been set to zero kW I think (need to confirm by studying more plots) that your system will never ever export solar panel power in excess of what can be consumed in real-time. So if your home load was say 1kW and the panel was producing 2.5kW and the inverter would offset the 1kW for the home load so there was no draw from the grid: and the excess of 1.5kW would be used to charge the battery. If the home load reduced to 0 kW the inverter would stop feeding 1 kW into the grid and the full 2.5kW would be used to charge the battery. However, once the battery is at 100% SOC any excess solar energy can no longer be stored in it; thus there can be the situation that there is no/next to no home load, high solar pv generation topping up the battery, the battery becomes full and all solar pv generation is terminated and the array current is deliberately reduced to zero Amps - or in other words pv generation ceases. It ceases because there is no where for it to be stored or consumed in the home and true export to the grid is forbidden by the backflow setting of +0000W. This is the 'self consumption' priority scheme.
To export surplus pv energy which you cannot store or consume in your home the scheme would have to be 'prioritise self-consumption and export/sell surplus'.
See for more explanation - you have the first set-up I reckon ;total self consumption any 'sale of excess' is prohibited at the moment by the backflow power being set at +0000W - you do have a generation meter for the reasons in para 3 above:
https://news.dualsun.com/news/lets-talk-about-pv-self-consumption/#:~:text=With%20%E2%80%9Cself%2Dconsumption%E2%80%9D%2C,meet%20the%20home's%20electricity%20needs.
This thinking - if correct - indicates why there have been no fault codes or alarms - it is the current mode of operation of your system for using and storing pv energy to minimise your import of electricity from the grid.- but to make no gain from selling any excess
[automerge]1600102186[/automerge]
If you log in, go to Devices, click on the blue tick beside your inverter and then open the 'Status' you will see that 'Self-use mode' aka 'Self-consumption has been selected.
1. You have a generation meter in the ac line from the inverter to the mains intake which does indeed clock up kWh?
2. Do you have a 'current clamp' attached around one of the electricity supplier's meter cables? It will look something like this:
Learn | OpenEnergyMonitor - https://learn.openenergymonitor.org/electricity-monitoring/ct-sensors/installation
It will be hard-wired back to the inverter or connected via a radio signal eg: Wifi.
3. On your electricity bill is the debit amount of electrical energy you have to pay for the difference between your electricity supplier meter reading and your pv generation meter reading?
4. On your bill is their a separate credit for surplus energy you have exported to the grid at a different rate to the units in para 3 - I wager there is not.
Its appears to me that your pv system is set up to optimise 'self-consumption' of solar energy in real-time and if that cannot be achieved ie: your home's load is lower in kW than that being produced at the time by the panels to then store the excess in the battery for use at other times.
Because your backflow(ie: net )export power setting has been set to zero kW I think (need to confirm by studying more plots) that your system will never ever export solar panel power in excess of what can be consumed in real-time. So if your home load was say 1kW and the panel was producing 2.5kW and the inverter would offset the 1kW for the home load so there was no draw from the grid: and the excess of 1.5kW would be used to charge the battery. If the home load reduced to 0 kW the inverter would stop feeding 1 kW into the grid and the full 2.5kW would be used to charge the battery. However, once the battery is at 100% SOC any excess solar energy can no longer be stored in it; thus there can be the situation that there is no/next to no home load, high solar pv generation topping up the battery, the battery becomes full and all solar pv generation is terminated and the array current is deliberately reduced to zero Amps - or in other words pv generation ceases. It ceases because there is no where for it to be stored or consumed in the home and true export to the grid is forbidden by the backflow setting of +0000W. This is the 'self consumption' priority scheme.
To export surplus pv energy which you cannot store or consume in your home the scheme would have to be 'prioritise self-consumption and export/sell surplus'.
See for more explanation - you have the first set-up I reckon ;total self consumption any 'sale of excess' is prohibited at the moment by the backflow power being set at +0000W - you do have a generation meter for the reasons in para 3 above:
https://news.dualsun.com/news/lets-talk-about-pv-self-consumption/#:~:text=With%20%E2%80%9Cself%2Dconsumption%E2%80%9D%2C,meet%20the%20home's%20electricity%20needs.
This thinking - if correct - indicates why there have been no fault codes or alarms - it is the current mode of operation of your system for using and storing pv energy to minimise your import of electricity from the grid.- but to make no gain from selling any excess
[automerge]1600102186[/automerge]
If you log in, go to Devices, click on the blue tick beside your inverter and then open the 'Status' you will see that 'Self-use mode' aka 'Self-consumption has been selected.
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See my comments below thanks
Is there any setting i need to change here I want to use power when the house, water, battery need it and once battery is full and house/water satisfied then export to grid so in future i get paif for excess (when the buy back system finally come on stream in Ireland)
Is there any setting i need to change here I want to use power when the house, water, battery need it and once battery is full and house/water satisfied then export to grid so in future i get paif for excess (when the buy back system finally come on stream in Ireland)
- Reaction score
- 4,325
I will read your reply above tomorrow. Meanwhile:
I cannot access the EPM settings options - perhaps you can and then relay them to me.
I also need to know the battery charge/storage option which has currently been selected - they are off-grid, auto or timed.
The Backflow power would need to be increased to a setting allowed in Ireland.
You'd need to confirm with your electricity supplier they will indeed pay for your excess or change to a supplier who will - not sure if you have several energy suppliers or a nationwide one.
You made need your system to be certificated by your installer or your electricity supplier if you want them to pay for your exports - I don't know what is required in Ireland. In UK payments for exports in the domestic setting are pittance - far better to self-consume, store or offset.
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Marconi in ireland it’s not an option to sell or offset excess yet.. I know crazy in this day and age but they are supposed to work towards it for end of 2021 with smart meters being installed etc. The system is fully certified etc already but I’m an early adopter in Ireland very few houses nationwide with PV arrays. I’m also going with a Tesla next year hence why I want to be sure the system is working as well as possible.
Can you tell me what you need regards EPM settings I’m not sure what you mean.
battery is set to timed but time settings are not input so it charges and discharges 24hours a day.
Also I’m adding below an image showing the settings for ireland Per the inverter. Note the down times for voltage over etc are only 40 seconds so seems to indicate this issue is either outside the inverter or the rules are being broken continuously for long lengths of time when the system goes down.
[
also see today’s status with battery full house drainage very little and export occurring on a sunny day.
QUOTE="marconi, post: 1657802, member: 87486"]
I will read your reply above tomorrow. Meanwhile:
I cannot access the EPM settings options - perhaps you can and then relay them to me.
I also need to know the battery charge/storage option which has currently been selected - they are off-grid, auto or timed.
The Backflow power would need to be increased to a setting allowed in Ireland.
You'd need to confirm with your electricity supplier they will indeed pay for your excess or change to a supplier who will - not sure if you have several energy suppliers or a nationwide one.
You made need your system to be certificated by your installer or your electricity supplier if you want them to pay for your exports - I don't know what is required in Ireland. In UK payments for exports in the domestic setting are pittance - far better to self-consume, store or offset.
[automerge]1600104690[/automerge]
[/QUOTE]
Can you tell me what you need regards EPM settings I’m not sure what you mean.
battery is set to timed but time settings are not input so it charges and discharges 24hours a day.
Also I’m adding below an image showing the settings for ireland Per the inverter. Note the down times for voltage over etc are only 40 seconds so seems to indicate this issue is either outside the inverter or the rules are being broken continuously for long lengths of time when the system goes down.
also see today’s status with battery full house drainage very little and export occurring on a sunny day.
I will read your reply above tomorrow. Meanwhile:
I cannot access the EPM settings options - perhaps you can and then relay them to me.
I also need to know the battery charge/storage option which has currently been selected - they are off-grid, auto or timed.
The Backflow power would need to be increased to a setting allowed in Ireland.
You'd need to confirm with your electricity supplier they will indeed pay for your excess or change to a supplier who will - not sure if you have several energy suppliers or a nationwide one.
You made need your system to be certificated by your installer or your electricity supplier if you want them to pay for your exports - I don't know what is required in Ireland. In UK payments for exports in the domestic setting are pittance - far better to self-consume, store or offset.
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[/QUOTE]
No lights never flicker.
I also upgraded my supply from 11-16 KVA supply a few weeks back wondering if that could help the issue but no idea If it makes any difference.
QUOTE="marconi, post: 1657722, member: 87486"]
Do your home lights ever flicker on and off? Or dim/swell in brightness for a few seconds?
[/QUOTE]
I also upgraded my supply from 11-16 KVA supply a few weeks back wondering if that could help the issue but no idea If it makes any difference.
QUOTE="marconi, post: 1657722, member: 87486"]
Do your home lights ever flicker on and off? Or dim/swell in brightness for a few seconds?
[/QUOTE]
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Could you give me some other days when the inverter stopped generating power please - what I have noticed is that if one looks at inverter internal temperature and dc voltage pv1 against time for the 18 Aug 20, the drop in pv1 voltage co-incides with the inverter internal temperature reaching 59.8C. There is this notice under the 'Temp' tab the bold, underlined italicised text is relevant:
--->
IGBT (Core) Temperature
When IGBT temperature is lower than its max. tolerance temperature, inverter can run stably.
Inverter Ambient Temperature
Inverter internal air temperature
Notice: Usually, IGBT temperature is 20 ℃-30 ℃ higher than inverter ambient temperature.
<---
So, maybe at maximum generation, on a hot day in your loft the IGBT(Core) temperature is of the order 59.8 + 30 = 90C. All semiconductors ( in this case an Insulated Gate Bipolar Junction Transistor IGBT) have maximum junction temperature limits of the order 150C-175C. Normally the semiconductor devices are operated at temperatures much lower than the maximum in order to safeguard their reliability and lifetime. See: First few paras of:
https://www.analog.com/media/en/training-seminars/tutorials/mt-093.pdf
There will necessarily be a thermal gradient between the junction of the IGBT (a semiconductor power switch necessary for the conversion of dc into ac) and the the ambient air flowing of the heat sink of the inverter box. It may be then that at on very sunny days, with high ambient temperature in the loft and peak pv power generation the IGBT core temperature has been exceeded causing a shutdown of generation.
Have a look at the plot for 18 Sep 20 of DC voltage PV1, Ac Output Total Power and internal temperature C against time. You will note a period of very high pv generation (6.3kW) before the shutdown and a steady rise in temperature. The generation starts again when the internal temperature is 40C. The generation does not look stable, fluctuating markedly, which seems odd to me on a clear very sunny day without clouds. Could you post this plot for others to look at who may be following this thread - I cannot do it for some reason.
Anyway, to pursue this line of analysis I need some other times/days when the inverter shutdown to see if the same correlation is apparent.
--->
IGBT (Core) Temperature
When IGBT temperature is lower than its max. tolerance temperature, inverter can run stably.
Inverter Ambient Temperature
Inverter internal air temperature
Notice: Usually, IGBT temperature is 20 ℃-30 ℃ higher than inverter ambient temperature.
<---
So, maybe at maximum generation, on a hot day in your loft the IGBT(Core) temperature is of the order 59.8 + 30 = 90C. All semiconductors ( in this case an Insulated Gate Bipolar Junction Transistor IGBT) have maximum junction temperature limits of the order 150C-175C. Normally the semiconductor devices are operated at temperatures much lower than the maximum in order to safeguard their reliability and lifetime. See: First few paras of:
https://www.analog.com/media/en/training-seminars/tutorials/mt-093.pdf
There will necessarily be a thermal gradient between the junction of the IGBT (a semiconductor power switch necessary for the conversion of dc into ac) and the the ambient air flowing of the heat sink of the inverter box. It may be then that at on very sunny days, with high ambient temperature in the loft and peak pv power generation the IGBT core temperature has been exceeded causing a shutdown of generation.
Have a look at the plot for 18 Sep 20 of DC voltage PV1, Ac Output Total Power and internal temperature C against time. You will note a period of very high pv generation (6.3kW) before the shutdown and a steady rise in temperature. The generation starts again when the internal temperature is 40C. The generation does not look stable, fluctuating markedly, which seems odd to me on a clear very sunny day without clouds. Could you post this plot for others to look at who may be following this thread - I cannot do it for some reason.
Anyway, to pursue this line of analysis I need some other times/days when the inverter shutdown to see if the same correlation is apparent.
Last edited:
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https://voltaconsolar.com/DOWNLOAD-FILES/Solis/Solis-RHI-(3-5K)_Installation Manual Voltacon.pdf
1. Re: Fig 3.3 - Meter Communication socket - Is anything connected to this socket?
2. Re: Your # 37 - the power figures do not balance. Power in from solar and battery is 5.6kW and power out for consumption and export to grid is 5.16kW - a difference of 0.44kW being apparently dissipated as heat in the inverter box - if the readings are correct. Rather a lot of thermal heating inside the inverter box.
3. It appears from the power figures that at least one of the grid power or consumption powers is being measured in order that the other can be recorded. Maybe the consumed power is being measured by a current clamp and not the export grid power. Could you have a look around the consumer unit for a clamp - no need to open it up. It would be helpful if you took some photos and post them for me to look at of your loft inverter installation, your supply metering, inverter metering and consumer unit being careful to capture the cable routes and switchgear. And also for the data logger.
1. Re: Fig 3.3 - Meter Communication socket - Is anything connected to this socket?
2. Re: Your # 37 - the power figures do not balance. Power in from solar and battery is 5.6kW and power out for consumption and export to grid is 5.16kW - a difference of 0.44kW being apparently dissipated as heat in the inverter box - if the readings are correct. Rather a lot of thermal heating inside the inverter box.
3. It appears from the power figures that at least one of the grid power or consumption powers is being measured in order that the other can be recorded. Maybe the consumed power is being measured by a current clamp and not the export grid power. Could you have a look around the consumer unit for a clamp - no need to open it up. It would be helpful if you took some photos and post them for me to look at of your loft inverter installation, your supply metering, inverter metering and consumer unit being careful to capture the cable routes and switchgear. And also for the data logger.
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