Solis RAI 3K AC - no discharge, shows as operational but no contribution to household load?

[Umski]

Hello folks,

Noob here though hoping there's a bit more of a knowledge base than some of the other forums!

Background - I already have 4kWP of PV on a SolarEdge inverter and picked up the Solis RAI AC-coupled with a view to using 48V of leisure batteries that I originally had for a UPS.

The Solis is installed and claiming to be operational but seemingly never discharges and hence contribute to the household loads. I have 3 lines of thinking why

1. It doesn't like the battery config (I have a US5000 on pre-order but this was a stop gap)
2. Settings - I'm sure anyone with a Solis will agree it's clunky and the TechView app is next to useless (no installer password it seems?)
3. CT input and algorithm not quite picking up the power flow and thus assuming everything is balanced

So here are some puzzlements that might help as the settings are a little bizarre:

I set up the batteries as per the 'Battery Select' menu and set the various volts/currents etc

I changed the Storage Energy Set>CT Install to PV Inverter (rather than grid) - this makes sense as it is clamped around the PV leg (though it overreads it seems) - the CT is directional and I have double checked this

Stg Mode Select>Self use - but has a hidden menu that allows access to the 'time of use' settings - so I disabled 'charge from grid', again no difference
Export Power Set>
EPM>On (export power management)
Backflow power (set to 0000W)
Failsafe>On (to comply with G100

So I can't figure out if it's due to me using Lead Acid batteries or that the way it is calculating the net power that the house is using is inaccurate - the Acrel meter seems to be pretty close to the nearest few Watts (again double checked orientation), but when I look in Information>System Info menu the 'grid power' doesn't seem to make sense - I would have assumed that it is using this value to figure out how much power to output...but it's not clear if a positive or negative value indicates import or export?

Any thoughts or experience of the quirks of the Solis welcomed - thanks!

 

[SeaGal]

If the CT clamp is around the inverter output, rather than house to grid, then by setting
"EPM>On (export power management)
and Backflow power (set to 0000W)"
the inverter will not allow any output past the clamp. So try moving it to measure house to grid current.

Make sure the time of use is set to stop and/or charge and discharge times are all set to 00:00

 

[Umski]

If the CT clamp is around the inverter output, rather than house to grid, then by setting
"EPM>On (export power management)
and Backflow power (set to 0000W)"
the inverter will not allow any output past the clamp. So try moving it to measure house to grid current.

Make sure the time of use is set to stop and/or charge and discharge times are all set to 00:00

Thanks, yes the Acrel meter CT is already on the meter tail so can't go any further downstream - the other CT that measures the PV is on the PV inverter output - all the info in the Information>Meter Info and CT info tally with what I am seeing (I have an open energy monitor set up with 2 CTs measuring PV and net grid). The one bit of information that doesn't quite make sense is under Information>System Info where 'Grid Power' has a very low value and fluctuates from + to - I can't figure out if this is what it is for (i.e. aiming for zero grid power) and hence it is completely ignoring the Acrel reading and *thinks* the grid power is zero or close to already.

Yes double checked the time of use and this is set to stop and I also set all the values to 00:00 to be on the safe side.

Any further thoughts welcomed - does anyone else have the RAI (AC coupled) rather than the RHI which are subtley different due to the Acrel meter and CT arrangement?

 

[SeaGal]

We have an RHI hybrid which also has an Acrel CT based power monitor (and also an open energy monitor too). AFAICR, the Solis system info will show the readings (power and voltage) from the Acrel and update them every second.

I'd suggest checking what the Acrel itself shows on its LCD display for power (& voltage if you like) and compare that to what the Solis shows. If the Acrel is not showing the expected power on its LCD, then maybe one of the CT clamp's wire is loose where it connects to the Acrel or the CT is faulty?

I'm assuming that the Solis is reporting that the RS485 connection is OK and there are not any MET_Comm failures showing under alarm messages? You could double check that by temporary undoing the RS485 connector on the Solis to ensure that does generate an alarm. Also, is the Acrel's activity LED flashing once a second, to show it is responding to data requests from the Solis?

 

[Umski]

Thanks SeaGal, after some serious head scratching and taking your comments on board I have some success at last - I am an idiot - I had wrongly (though logically) assumed that having the meter CT on the neutral tail but facing the opposite direction would be okay, but again I slept on it and managed to shuffle it round in order to squeeze the CT on to the live tail (my energy monitor is just measuring current whether positive or negative so doesn't care that it's on neutral) - it seems the Acrel does too but the Solis needs something else data wise and hence the CT needs to be on the live side and on reflection it is looking to balance current going back to the grid which would happen via the live leg (at least that's my thinking looking at the way the power output is measured).

If it helps anyone else, here were my observations (a bit weird as I would consider the opposite!)

Information>System Info:
Grid power = positive when discharging, negative when charging

Information>Meter info:
Meter Power = positive on Export, negative on import

Anyway, so it started playing and at least for a short period as the PV dropped off did it's thing. I then have a couple of further snags but the fundamentals seem to be okay at least. My hot water diverter uses an 'energy bucket' concept, rather than pure power and so when it sees any 'export' energy (over time) it fires up the triac and occasionally tries to draw energy from the Solis, which it happily obliges too as it is also trying to balance the import/export - unfortunately this also happens with no PV (I think a simple AND statement should solve this so that when there is no PV at all, the diverter doesn't think there is excess energy being pushed to the grid). I can't at the moment think of a way to prevent this during the day - the code wasn't mine but I have tweaked it to suit, the hardcore loop part is harder to interpret (my electrical engineering and associated maths is a little rusty after 20 years sat behind a desk slowly allowing my brain to turn to mush!)

Second, is I was pleased to see my net import drop to zero at dark (though I need to add another CT to measure the Solis charge/discharge and then the associated addition/subtraction for it to make sense) - that lasted from around 5pm to 1am which I was a little disappointed by but then I only have a 65Ah bank and that limits me to a theoretical 1.6ish kWh, but at the low level voltage, it then just drops off completely - I can see why lead acids are a pain in the backside. Today it then recharged and continued as it should - my first experience was that I had to do a force restart of the HMI (new one to me, I've always considered it a MMI or UI) for it to then work as it should again (not what I want to be doing every day!)

Last tweak I may do to extend the run time, is to limit the discharge current which I'd set at 40A (giving me 2kW for using say the kettle or microwave) but the lead acids just won't sustain that and pull the voltage down and then it cuts out. I am charging at max 13.5A (0.2C value) but I think to preserve their life I'm an going to aim for maximum run time for background loads and limit the discharge to 10A (500W roughly) and import any excess. Roll on the Pylon US5000 which is on pre-order!

Thanks for your input, it made me think and hopefully this debacle will help others with the Solis!

 

[SeaGal]

Thanks SeaGal, after some serious head scratching and taking your comments on board I have some success at last - I am an idiot - I had wrongly (though logically) assumed that having the meter CT on the neutral tail but facing the opposite direction would be okay...

Result

Everything that goes up has to come down again - putting the clamp on neutral in opposite direction should work just fine. The Live and Neutral should be generally balanced current wise (apart from momentarily with a sudden inductive load) - if they weren't an RCD would be detecting a fault.

So, I'm wondering whether there was a dodgy connection on the Acrel/CT that has been rectified (excuse the pun) by moving its location? Not that is matters any more as it's working. Have sent you a pm too.

 

[Umski]

Result

Everything that goes up has to come down again - putting the clamp on neutral in opposite direction should work just fine. The Live and Neutral should be generally balanced current wise (apart from momentarily with a sudden inductive load) - if they weren't an RCD would be detecting a fault.

So, I'm wondering whether there was a dodgy connection on the Acrel/CT that has been rectified (excuse the pun) by moving its location? Not that is matters any more as it's working. Have sent you a pm too.

Yes it's weird, I don't understand it either, but as you say it's working now!

 

[parody]

Hi @Umski @SeaGal - I registered here because reading your posts was like reading my experience over the last couple of days. I've basically gone through the exact same troubleshooting process for why the batteries won't charge or discharge with a very similar set up.

I have 170ah of 12v (x4 = 48v) LA batteries and the same inverter, added to an existing array. I don't have the meter, my CT is on the live of the grid and set correctly on the inverter. In Solis cloud, if you add all devices to the same "plant" you get the same information as you would with a CT on the inverter anyway. The CT appears to be correct in terms of direction (at night I am importing).

When I rely on self use mode (that is, I expect excess solar to charge the battery and demand to use it) I can only get one or the other working. Like you, I found restarting it would cause the correct behaviour for that point of time but only for a short while.

If I set up time of use charging, it works fine - I can set some general sun-time hours for slow charging through the day (12.5A) and night time hours for slow/background offsetting discharge (7A). But even then, I don't see excess solar top up the battery more than what I set the time of use charge limit to.

I suppose I can make timed mode work (it would also care for the LA batteries better than constant small charge / discharge cycles) but it is too easy then to charge from the grid (or even discharge to the grid - that should be prevented by the export limit I guess).

I've also seen some real whacky numbers in Solis cloud like exporting more than I am producing with no house load at all (apparently) despite the inverter CT info and independent energy monitor agreeing on a much smaller export value.

My best scenario would be:

• Slow time-of-use charging during sunlight hours + boosted by excess solar production when available. From what I understand, this allows the LA battery condition to be maintained with full charge / discharge cycles, as well as not wasting excess back to the grid
• Demand based usage overnight only - again to help maintain the batteries but not feed battery power back to the grid.

This has led me to wanting to see if I can upgrade the firmware and do a "factory reset" but I can't see to find how to do that anywhere. I see many different menus documented for this inverter which leads me to think my firmware is old - for example I don't have a self-use menu - only time-of-use which I disable to default to self-use.

What have you ended up with now? Is it working?

Thanks, good luck with it even if you don't reply.

 

[Umski]

Hello @parody , welcome to the pain! Do you also have the RAI (AC coupled)? When you say you don't have the meter, is that the Acrel that measure the voltage and phase but also the import/export. I don't know off the top of my head if the hybrids (RHI) have this extra meter as I assume it 'knows' what the PV is and can thus use just a separate CT for the import/export and derive the volts etc from the grid connection?

I did have the system working for short periods without any intervention but I think one of my LAs is faulty (the magic eye went black) and so it seems to be pulling the system down which means I get around 3-4 hours only with background loads - I limited it to 300W output and kept the low voltage protection at 48V (there's a bit of hysteresis to allow for the 12.1V cut-off as 50% DoD).

The self-use setting seems to be implicit if selected (it should show this on the main display at idle), but you can then enter the ToU settings if you go further into the menu - I didn't need this so I set it all as off and changed the times to 00:00 for all just to be on the safe side.

As far as Solis Cloud goes, it seems to be pretty useless as I monitor separately with OpenEnergyMonitor on a per second basis and when that's running it seems accurate so I don't rely on that much - I do however keep an eye on the 'advanced information' menu as this shows the charge/discharge value.

I am due to get my Pylon US5000 next week now so I can put the LAs behind me - it's annoying however as I think one of them is bad (magid eye showing as black) and currently trying to get batterymegastore to honour the warranty which they seem to be throwing back to me as if it's down to me to prove it somehow - not impressed with them!

 

[parody]

Hi @Umski

Yes same AC couple RAI inverter. It only has the CT around the live to grid, where it (correctly as far as I can tell) measures the positive or negative flow. As I understand that is all the a acrel is doing via a CT too. I'm not sure why it needs the acrel other than, perhaps, to handle 3 phase circuits (rather than needing 4x CT inputs on the inverter itself). My solar is split across 2 inverters so I can't use the CT on the inverter side anyways.

I've also noticed that some RAI manuals show that the acrel is included and others it is not, I would guess dependant on the market.

I've basically given up on the LA, they are up for sale. I have seen some sellers of the RHI inverter saying they will not honour warranty if used with LA batteries because the inverter cannot measure the SOC well. I wonder if that is the key issue - the inverter is not doing very well at knowing when the battery can charge / discharge. I never got it working automatically on self use without a reset at different times of day. Perhaps when it starts up it gets something right with the LA SOC.

What version of firmware are you running? I've not heard back from ginlong yet about an upgrade. I had hoped that might fix things.

I'll have a look at open energy monitor too, thanks for the pointer.

 

[Umski]

Hi @Umski

Yes same AC couple RAI inverter. It only has the CT around the live to grid, where it (correctly as far as I can tell) measures the positive or negative flow. As I understand that is all the a acrel is doing via a CT too. I'm not sure why it needs the acrel other than, perhaps, to handle 3 phase circuits (rather than needing 4x CT inputs on the inverter itself). My solar is split across 2 inverters so I can't use the CT on the inverter side anyways.

I've also noticed that some RAI manuals show that the acrel is included and others it is not, I would guess dependant on the market.

I've basically given up on the LA, they are up for sale. I have seen some sellers of the RHI inverter saying they will not honour warranty if used with LA batteries because the inverter cannot measure the SOC well. I wonder if that is the key issue - the inverter is not doing very well at knowing when the battery can charge / discharge. I never got it working automatically on self use without a reset at different times of day. Perhaps when it starts up it gets something right with the LA SOC.

What version of firmware are you running? I've not heard back from ginlong yet about an upgrade. I had hoped that might fix things.

I'll have a look at open energy monitor too, thanks for the pointer.

Ah okay, where abouts are you? In the UK at least, I *think* the Acrel is an additional measure for compliance so that it has 2 means of 'seeing' when the grid is lost and cutting out - the Acrel connects to the RAI via a RJ45 whilst the PV is on a two pin CT. So if I understand, you are using the port labelled CT and have set the relevant setting to 'grid' rather than PV and you have no Acrel at all?

I noted there is a v1 and v1.1 manual for the RAI, the latter matched what I have which confused me for a while.

If I understand the method for charging LAs it's simply using a charge voltage of 14.4V per battery with a float that can be set to a value - 13.5V/batt for flooded which is what I've been using. Again using the OEM I can see that it charges at full whack for a period - essentially bulk charging and then reverts to a periodic charge cycle, but again as mine have been playing up this is just an observation. I don't think it's possible to measure SoC accurately with the LAs - I guess it estimates based on the capacity and the amount of power it charges/discharges with over each day?

Firmware is 11000E though apparently there is a 130010 (I know of another forumite that couldn't get their Pylon BMS to talk so they remotely updated it - turns out the connection hadn't been made inside the Solis!)

 

[parody]

My inverter doesn't even have both an Acrel and Meter input - it is a single port labelled CT/Meter than only accepts a 2 wire connection. If you compare these two manuals you'll see the different contents and different layout of the ports:

RAI-3K-48ES-5Guk

Solis energy storage inverter is a good choice for on/ off-grid integrated storage solutions 1. Higher incomes: select the electricity consumption mode in real time according to the market price; 2. High independence: can be operated out of the power grid; 3. Higher efficiency: new components...

www.ginlong.com

https://www.ginlong.com/rai_inverter1/11137.html < this is like mine

But yes I have set CT to grid and can still set to precent export on power loss.

Strange, my firmware is "V07". I don't see one listed with your designation in the battery list (https://www.ginlong.com/uploads/file/Solis_Leaflet_Battery_matching_V2,0_2022_10.pdf)

I'm due to collect my lifepo4 battery later so I'll report back what I find. The LA sold no problem.

 

[parody]

@Umski

I have just finished installing the 5kw lifepo4 battery. I have to say, it's brilliant. Worked first time, all comms working. It's great to see the inverter reporting battery SOC and other data.

I'm sure when you receive your pylontech, your troubles will be behind you.

If anyone needs a quality CATL based lifepo4 battery for a great price without waiting 2 months, PM me and I'll share some contact details.

 

[Umski]

@Umski

I have just finished installing the 5kw lifepo4 battery. I have to say, it's brilliant. Worked first time, all comms working. It's great to see the inverter reporting battery SOC and other data.

I'm sure when you receive your pylontech, your troubles will be behind you.

If anyone needs a quality CATL based lifepo4 battery for a great price without waiting 2 months, PM me and I'll share some contact details.

Good to hear that worked Yes due to get my Pylon Wednesday - its the 5000C so fingers crossed - I think worst case is to set it up manually with settings that Victron suggest - I genuinely don't understand the firmware references - the 11000E is what the inverter itself shows under general information>SoftVer

I'm guessing the SKU you have is different in large parts - both hardware and software - whereabouts are you located?

 

[Derek De Leon]

@Umskie,
I am in UK with the Solis RAI version with the Accrel meter and the CT, Firmware version is also 11000E.

I use a Solic200 energy diverter which operates on a hairtrigger threshold. I fitted a Henley block between the consumer unit and the Electricity board meter. I connected an additional consumer unit to the henley block and that is where the Solic sources its electricity from. The Accrel clamp is on the inlet to my main house consumer unit, so when the Solic200 is consuming power the Accrel clamp is unaware. The Solic CT clamp is at the electricity board meter.This seems to work fine.

 

[thegrazingcow]

Joining the RAI-3K-48ES-5G and US5000 hype train, I'm interested to hear how your setup process goes @Umski. I've just finished my setup of a kit from ITS in the UK, and am having some teething issues. Almost guaranteed to be related to personal incompetence, but I'm currently failing to get consistent results. The setup I'm going for is charging from excess solar ONLY, no charging from the grid, and supporting any power loads from the house.

The issues seem to vary with time for me, but include:

1. The inverter will cycle between drawing power from the battery and charging it, even when there is no excess solar. e.g. at night, the following pattern occurs.
2. Sometimes the inverter will decide to neither charge nor discharge the battery. The usual suggestions I've read regarding setting backflow, EPM, storage mode select either to AUTO (aka everything to off) I've not had much luck with. The issue I'm finding is that it's not behaving particularly deterministically, making it harder to debug. In its current state, I'm calling it a night with it in this state after an evening of attempting to figure it out...

My number one suspect for a lot of this is the CTs, as I've read somewhat mixed things regarding their placement. Some state to install both the Acrel CT (the CT connected to the Acrel meter, which is then connected to the 'Meter' port on the Solis inverter) and the Solis CT (the CT connected to the 'CT' port on the Solis inverter) on the live tail straight after the energy supplier's meter. Others like the manual (see below) seem to clearly show the Acrel CT on the live tail after the energy supplier's meter, and the Solis CT on the output of the solar inverter (in my case not a single inverter, but IQ7+ microinverters per panel, so the Solis CT on their radial). And other places, somewhere in-between!


There's also a 3. issue, which was at one point when it all seemed to be working as intended, but the power draw had a significant wander whilst it chased net 0W to the grid, with the ideal solution sounding like something either available in a newer firmware (currently 11000E like you guys) or on other inverters, which is to set the export limit to negative values so that it can begin to derate the output before anything is actually output to the grid. But, alas, only positive values available on my unit ¯\_(ツ)_/¯

So yeah, let me know how it goes if you have a chance!

Will

 

[Umski]

Joining the RAI-3K-48ES-5G and US5000 hype train, I'm interested to hear how your setup process goes @Umski. I've just finished my setup of a kit from ITS in the UK, and am having some teething issues. Almost guaranteed to be related to personal incompetence, but I'm currently failing to get consistent results. The setup I'm going for is charging from excess solar ONLY, no charging from the grid, and supporting any power loads from the house.

The issues seem to vary with time for me, but include:

1. The inverter will cycle between drawing power from the battery and charging it, even when there is no excess solar. e.g. at night, the following pattern occurs.
2. Sometimes the inverter will decide to neither charge nor discharge the battery. The usual suggestions I've read regarding setting backflow, EPM, storage mode select either to AUTO (aka everything to off) I've not had much luck with. The issue I'm finding is that it's not behaving particularly deterministically, making it harder to debug. In its current state, I'm calling it a night with it in this state after an evening of attempting to figure it out...

My number one suspect for a lot of this is the CTs, as I've read somewhat mixed things regarding their placement. Some state to install both the Acrel CT (the CT connected to the Acrel meter, which is then connected to the 'Meter' port on the Solis inverter) and the Solis CT (the CT connected to the 'CT' port on the Solis inverter) on the live tail straight after the energy supplier's meter. Others like the manual (see below) seem to clearly show the Acrel CT on the live tail after the energy supplier's meter, and the Solis CT on the output of the solar inverter (in my case not a single inverter, but IQ7+ microinverters per panel, so the Solis CT on their radial). And other places, somewhere in-between!


There's also a 3. issue, which was at one point when it all seemed to be working as intended, but the power draw had a significant wander whilst it chased net 0W to the grid, with the ideal solution sounding like something either available in a newer firmware (currently 11000E like you guys) or on other inverters, which is to set the export limit to negative values so that it can begin to derate the output before anything is actually output to the grid. But, alas, only positive values available on my unit ¯\_(ツ)_/¯

So yeah, let me know how it goes if you have a chance!

Will

Hi @thegrazingcow - welcome to the fun! My delivery from ITS is due today - no sign yet! I have a couple of thoughts based on my experience so far:

1. CTs - definitely check the orientation and my placement is Solis CT on the PV output and Acrel on the live tail prior to the CU - from what you say this should be fine - you can check what the Solar CT and Acrel CT are measuring via the information menus (weirdly placed under Information>Meter info (Acrel) and CT info) - the Acrel reading should match what the Solis shows

Also check that under Advanced Settings>CT install the setting is PV inverter

I found that the PV CT over-reads somewhat, but in reality the Solis uses the import/export balance from the Acrel

2. Having not had the Pylon yet, are you able to derive anything from the battery comms side - is it all working properly from what you can see? I wonder if the weird charge during the night is a forced charge? Is the Pylon reporting good SoC? Is your battery setting just on 'Pylon' or user defined? I was wary that the support list only includes the 2000 and 3000 series officially...

3. When it has been online (I've not bothered the last week due to low PV anyway), it tracks net-zero pretty well - it can be a bit slow to react if there is a surge load such as the fridge coming on etc, but generally my monitoring reports zero import. The export settings go up in increments of 100W I recall - I don't want any export so I set that to zero. In a way it works in a similar way to my DHW diverter in that most energy meters can only register 1Wh in either direction (hence the 'bucket' naming) - I have an anaolgue meter which is 5Wh per turn of the wheel - I can see it bouncing back and forth and when stable just sits there doing nothing which is what the aim is

Will report back as and when I get the Pylon

 

[Umski]

Pylon delivered finally, bit later than expected so not sure I'll be able to fiddle until the weekend I can see the benefits of having the less weighty US2000 or US3000 now having tried to move the box!

 

[SeaGal]

Benefits of more kWh trump the weight ?️‍

 

[parody]

Good to hear that worked Yes due to get my Pylon Wednesday - its the 5000C so fingers crossed - I think worst case is to set it up manually with settings that Victron suggest - I genuinely don't understand the firmware references - the 11000E is what the inverter itself shows under general information>SoftVer

I'm guessing the SKU you have is different in large parts - both hardware and software - whereabouts are you located?

I'm in the UK... I'm not sure why there is this variation of models! I wonder, if those with meters have issues, if it is worth trying the direct CT method and setting the clamp location appropriately. I am not able to use the clamp on the inverter anyway, because I have 2 inverters located far apart. I would be happy to use a meter - I looked to buy one but only found results in China.

I genuinely think the issues with the inverter + lead acid is all related to the ability accurately measure the SOC.

So far, so good-ish with my lifepo4. I have found:

1. When configuring it (as a PYLON) you can only set the minimum SOC. I would have liked to be able to restrict the rate at which it charges and discharges (I know we have 3kw to play with, but I'd rather trickle it out at 1kw than dump it at 3kw). I have been trying to find a setting that would allow me to de-rate the inverter. I found "power parameter" and "power rate limit" but can't find what they mean. Does anyone know?
2. I set the minimum SOC to 20% initially. I have found that while it stops there, it continues to drain slightly overnight, and then has a sudden burst of grid sourced charging in the early hours. I assume this is a forced charge. I understand the inverter itself runs on DC (this may be why @thegrazingcow sees the pretty graphs - powering the inverter itself and floating the battery likely causes some constant in/out). I have now set it to 25% minimum SOC to see what happens.
3. I seem to be maintaining a grid import of 200w, based on my real-time smart meter, while the solis is reading zero import/export at the CT. I had to extend my CT which I did with speaker wire (just what I had available). I believe the reading error could be to do with that, so I will be changing to a shielded twister pair CAT6 cable. I also measured the AC voltage at the inverter with a multimeter and compared it to what the inverter sees (real time). I found it needed a correction of -0.6v which improved the reading error by about 50w.

I was surprised yesterday to have charged the battery to 70% on a clear autumn/winters day. I think I will be needed another battery in the summer because I am also increasing the array size and inverters - I'm getting 2x3kw (currently 1x1.5kw and 1x2kw) with export limitation).

I'm really interested to hear your results with the new pylon @Umski .