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RonanIrl

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  • #37
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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.

12C6BEA2-D8E9-4621-898E-2A9A2F0869DF.jpeg[

also see today’s status with battery full house drainage very little and export occurring on a sunny day.

64631EE8-8E98-40C1-91C9-C3C3A20B692A.pngQUOTE="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.
Post automatically merged:

[/QUOTE]
 
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R

RonanIrl

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  • #38
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]
 
marconi

marconi

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Arms
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. :)
 
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marconi

marconi

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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.
 
marconi

marconi

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RonanIrl: I found this installation video:

RHI-(3-5)K-48ES - https://solisinverters.com.au/product/rhi-3-5k-48es/

Could you look at it and tell me any similarities or differences? At the moment I am particularly interested in the bits at 5min08s on the data stick (-do you have one?) and from 5min15s onwards on the meter and current clamp.

This is also interesting on how the Solis hybrid inverter reduces its power output at the temperature rises:

Inverter Temperature De-rating - https://usservice.ginlong.com/support/solutions/articles/36000074739-inverter-temperature-de-rating

You will see a table which says that the inverter degrades in power and then shuts down at 60C. Food for thought. But you do not it seems get an OV TEMP fault code or alarm which is perplexing.

I note your inverter, at least beneath it, does not have the minimum 300mm clearance and there is what looks like pyramid loft insulation.

PS: I declare now: if it was my installation, it would not be in the loft.
 
Wilko

Wilko

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Arms
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
Hello M - just triggered me on the conversion efficiency of the Invertor. For sure no Invertor is 100% efficient and these readings imply 1- 44/560 = 92%. So 8% in heat, hmmm ... smoking gun? :)
61603118-7D3D-43E4-8E15-E3F06C06B8CB.jpeg
 
R

RonanIrl

  • Thread Starter Thread Starter
  • #43
See below answers


Could you give me some other days when the inverter stopped generating power please -

May 30
June 2/16/19


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.

The IGBT temp is a new measurement in the last firmware and SOLIS have looked into this already for my issue it was same on the old inverter so its not that accoring to them. The invetrer livese in a dark cold plant room so termpertaure there is never above 20, ite well ventillated and no heat sources on warm days.

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. :)
[/QUOTE]
 
R

RonanIrl

  • Thread Starter Thread Starter
  • #44
See Responses Below

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?
Yes black plug heading off somehwre

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.

Dont owrry about that i had the backup meter swithed off in options ithis includes heat energy, internal energy to run the inveter and engery diverted to a second backup battery if instaleld, now I turned it back on the figures balance I actually had my installer on the blower about it last night and asked him why they didnt add up, once i enabled backup measurment again it did weird...id say he is sick of me by now.

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.

At the moment im not in a position to acces the loft.. i do know there are clamps up there but could be anywhere on the long runs. Also gained this nugget of info on the call with the installer.
 
R

RonanIrl

  • Thread Starter Thread Starter
  • #45
Responses as below

RonanIrl: I found this installation video:

RHI-(3-5)K-48ES - https://solisinverters.com.au/product/rhi-3-5k-48es/

Could you look at it and tell me any similarities or differences? At the moment I am particularly interested in the bits at 5min08s on the data stick (-do you have one?) and from 5min15s onwards on the meter and current clamp.

Yes i have a data stick thats how the appa and webiste portal receive info via my wifi and firmware updates are deployed by SOLIS or me manually if sent.

Yes the meter is plugged in but clamp is up in the loft somwhere

The system is deifitly setup to know when grid is available and lines are clamped to measure


This is also interesting on how the Solis hybrid inverter reduces its power output at the temperature rises:

Inverter Temperature De-rating - https://usservice.ginlong.com/support/solutions/articles/36000074739-inverter-temperature-de-rating

You will see a table which says that the inverter degrades in power and then shuts down at 60C. Food for thought. But you do not it seems get an OV TEMP fault code or alarm which is perplexing.

Solis looked into this also and said its not the issue that said inverter hyper clipping was my initail though what could be causing this


I note your inverter, at least beneath it, does not have the minimum 300mm clearance and there is what looks like pyramid loft insulation.

Its actualy in a cold plant room dark side of the house, 1m from the ground Pyramids are sound proofing for my boiler which is in the same room but obviously off in summer. Sound pyramids give little insulation as they are open cell. Fault was happening well before the sound insulation was installed.

The air can circulate via vents an its always below 20 in there even in sumemr.

SOLSI and my installer have looke dat temperatrure and both came back as negative causing the issue.




PS: I declare now: if it was my installation, it would not be in the loft.
[/QUOTE]
 
R

RonanIrl

  • Thread Starter Thread Starter
  • #46
I agree the inveter cooling sink can get hot but accoring to SOLIS and the installer no hotter than any other installtion they have done and not the cause of the problem.



Hello M - just triggered me on the conversion efficiency of the Invertor. For sure no Invertor is 100% efficient and these readings imply 1- 44/560 = 92%. So 8% in heat, hmmm ... smoking gun? :)
View attachment 60838
 
marconi

marconi

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Arms
This afternoon I observed your real-time power figures for Generation, Grid, Battery and Consumption. It has clearly been very sunny where you live because the generation figures have been up in the 5-6kW range. The temperature of the inverter has exceeded 60C and you have had a shutdown of generation.

What I observed was 4600W output from the inverter to the CU; 900W consumption from the CU; 3700W export.

4600 = 900 + 3700.

With such high solar generation the battery should not be being discharged yet it was at a rate of 170W - this is not right. There is ample solar to supply the load and any export.

Here is the wrinkle; your installation is not set up to export because the backflow power is set to +0000W. And yet it is exporting - why?

I reckon the current sensor which monitors the glow of grid power into and out of your home is orientated the wrong way around - they have an arrow to indicate the supply and the CU direction - you could check this easily.

It might be though that the current clamp is orientated the correct way but its leads have been wired into the meter (which relays data to the inverter meter comms socket via an RS485 cable) the wrong way.

The wrong orientation of the current sensor or a switch over of its leads will reverse the sense of the data input on grid power flow so the inverter will interpret an export as an import and an import as an export.

For the self consumption mode of operation, any grid import is offset by the injection of inverter ac power of an amount conditional on the kW limit of the inverter pertaining at the time and the incident sunshine on the panels. The inverter does not use power from the battery for export to the grid - this battery is solely for home use.

A negative feedback loop controller ramps up PV generation until the ac output power cannot be increased any further. As the ac output power increases the imported power should reduce and if there is sufficient pv generation to zero import. However if the sense of the signal is incorrect the imported power signal rises and rises because it is actually representing export of the very same increased pv generation - a positive feedback loop - ie: export power becomes maximised. The inverter starts to get hotter.

When one studies the ac output power plot it cycles between maximums and a minimums in a way determined by the temperature related power output derating scheme, incident sunshine changes and load changes in the home. Eventually the inverter shuts down (or becomes unstable at higher temperature and looses sync with the mains) . It cools down, restarts and then carries on again.

Power figures right now: Gen 3.25kW, Load 0.9kW, Export 2.25kW Battery discharge 0.15kW
 
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marconi

marconi

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RonanIrl - you have seen this in my email to you.

Yes I did see the shutdown. I was observing the data and 'fortunately' I saw it happen. I hope my explanation in my last post of the EF makes sense; you must have covered positive and negative feedback which will be used in aircraft system controllers.

What made me explore positive feedback through an incorrectly orientated grid power flow sensor was the apparent oscillation of the total ac power output between peaks and lows when there was little home load; it could only mean this high solar power generation was being exported because it was not being consumed nor charging the battery because as noted the battery was discharging - something you noticed.

Once I had confirmed you were exporting shed loads of power in the self use mode in an oscillatory manner the most likely reason was going to be the sensor mistaking import for export and changing negative feedback into positive. The other give-away was the gradual temperature rise - it went over 60C when ac output was some 6kW - which instigates the derating of the power output to prevent damage to the power electronics.

An indicator was the pv1 current mimicked the total power generation (which was being maximised for export) and not the home load - for self consumption, once battery charging is subtracted it should follow the home load only - negative feedback control system in action to minimise imported grid power but never export.

Other key factors - all worked properly overnight when there was no pv generation available for export - as noted the battery will not be drawn on to export. At the moment the 150W odd discharge is making up for the inverter power losses and measurement errors.

What I do need to check further is you seem to be charging your battery from the mains sometimes - need to confirm but I don't suppose you want that to happen - I would not unless you have cheap rate electricity overnight that makes it worthwhile. I saw it during the day too though.
 
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