Scubadude's 8kW Deye / Canadian Solar / Shoto Hybrid Solar Installation

[Antonio de Sa]

7 minutes ago, RetiredDIY said:

Hallo Antonio,

My electrical engineering background and @Bloubul7quote of the regulations agree that back emf during system switching can cause you to lose the system as if you had a lightning strike. Some systems could be better than others BUT the rules are not there for nothing.

If your inverter - at any switching combination - shows a potential of more than 0.5volt between its INPUT E to N or its OUTPUT E to N OR you are nuisance tripping your EL device - you may have a potential problem. There are numerous publications that describe the effects of back emf during transfer switching whether it is manual or auto.

In my case I probably forced the issue in that I instructed the contractor to go through all the operating modes.

The intention was that I could prepare a SOP manual that would assist my household in case of emergency. It turned a pleasant day into a disastrous one.

@RetiredDIY Thanks for the info, I've just measured using my old Fluk 77  AC imput to inverter  N to E = 0,560 V ---- output of inverter N to E = 0,010 V

I think that maybe I should install another earth spike and connect to my main DB earth.

I lived in Angola for many years and was very difficult to get hold of earth spikes, usually the electrician there would use a old car radiator, I wonder if that will work.

[RetiredDIY]

We share the same instruments. Shows my age.

If you measured in ALL switching combinations you need go NO further.

The obvious errors don't exist.

[Bloubul7]

Just a note, but you need to measure it twice (with Eskom power on and with Eskom power off)

[Scubadude]

OK, so 10 days later I have a brand new inverter installed - the first unit had burns on the PCB where the cables connect, so I'm told, probably because of a faulty changeover switch that would momentarily bridge municipal and inverter power.  I now also have a super high spec new changeover switch, surge protector replaced, batteries properly earthed and the battery master/slave set up correctly (SOC LED display in sinc for the first time). 

Reconfigured the inverter myself, because by now I'm fully convinced installers dont know how to do it properly. So the only things outstanding now are minor rewiring of the DB, relabeling main DB, and me paying the final 20%.

Downside is every time the system gets worked on it looks a little less clean and a little more tatty. Seems, like with most things, solar is best done properly first time round.  Happy this testing experience is close to an end - "it simply was a dud installation" the electrican said.

That said, I'm quite excited to be able to watch my system remotely again - this is highly addictive!  Still struggling to set authorisation for my "installer account" on Solarman Pro, but the Deye helpdesk indicated they would be able to assist.  Lets see how it pans out.

Edited December 21, 2021 by Scubadude

[Scubadude]

OK, so I had a pretty good Whatsapp chat with Jessica from the Deye support desk.  It seems Solarman Pro is a 2nd generation monitoring app and cannot be authorised to view and manage Solarman PV and Solarman Smart user plants. 

The good news is Solarman Business is their 3rd generation monitoring and control platform.  It is a little buggy (like the web landing page https://pro.solarmanpv.com/login is down, but I managed to install the app on my phone and to authorise the Business user from my Solarman Smart desktop as plant admin.  So far I can see the plant, and it does provide more comprehensive data than both Solarman PV and Solarman Smart. To be able to manage the inverter remotely (which is what I'm really after), you need to set up sub-systems on the web app, which is currently down (as I mentioned). Videos below show it should ultimately be possible.

EDIT: It works in Edge but not Chrome ... lets see where this goes ...

 

 

Edited December 21, 2021 by Scubadude

[PowerUser]

15 minutes ago, Scubadude said:

OK, so I had a pretty good Whatsapp chat with Jessica from the Deye support desk.  It seems Solarman Pro is a 2nd generation monitoring app and cannot be authorised to view and manage Solarman PV and Solarman Smart user plants. 

 

The above is not correct. I have my SunSynk inverter linked to a plant in Solarman Smart and the same inverter linked to a plant in Solarman Pro. In Solarman Pro, in registered as the owner and I can view everything on both platforms simultaneously for the same inverter/installation.

 

But you cannot do changes remotely from Solarman Pro. That is not possible at least with SunSynk.

Edited December 21, 2021 by PowerUser

[Scubadude]

I did say buggy, right?

[Scubadude]

8 minutes ago, PowerUser said:

 

The above is not correct. I have my SunSynk inverter linked to a plant in Solarman Smart and the same inverter linked to a plant in Solarman Pro. In Solarman Pro, in registered as the owner and I can view everything on both platforms simultaneously for the same inverter/installation.

 

But you cannot do changes remotely from Solarman Pro. That is not possible at least with SunSynk.

It may have been posisble in the past but not anymore ...

[Scubadude]

15 minutes ago, Scubadude said:

I did say buggy, right?

Pinged Jessica again, and she quickly autorised me to make changes to my inverter setup ... So I retract my buggy statement for now. Suppose I cant share the Whatapp number publicly, but anyone who needs to have real time support is welcome to PM me.

Edited December 21, 2021 by Scubadude

[PowerUser]

5 minutes ago, Scubadude said:

It may have been posisble in the past but not anymore ...

I registered only about 3 months ago. Not sure if they changed something recently. But both Solarman Smart and Pro are still working today for the same installation for me.

[PowerUser]

1 minute ago, Scubadude said:

Pinged Jessica again, and she quickly autorised me to make changes to my inverter setup ... So I retract my buggy statement for now. 

Interesting. Can you please ask Jessica, if this functionality is available for Deye inverters only or for SunSynk as well?

[Scubadude]

I have Smart and PV (the first Solarman - not sure this is the right name) and I registered a Pro account, but it looks like they dropped support for Pro in favour of Business.  I have a feeling the new Sunsynk app is not much more than a rehash of this Business platform.

[Scubadude]

4 minutes ago, PowerUser said:

Interesting. Can you please ask Jessica, if this functionality is available for Deye inverters only or for SunSynk as well?

Sent you her number by PM

[PowerUser]

52 minutes ago, Scubadude said:

Sent you her number by PM

My inverter is SunSynk and not Deye, so I doubt Deye support will respond to me. Anyway, I registered a Solarman Business account and maybe will ask Solarman support to migrate my plant from Pro to Business.

[Sc00bs]

On 2021/11/28 at 8:05 AM, Nitrious said:

Well EV's are on their way, so what works today may well not work once the move away from ICE vehicles begins, I've begun planning for around 24x 450w total panels for that occurrence. Lets not forget water, another rapidly increasing cost, so borehole is on the way, yet another energy requirement to be added, along with air to water for the kitchen. 

Result would be never paying for water, lights or fuel ever again. Worth it? definitely, but maybe I'm just crazy.

I have 28 x 455w panels on 8kw Sunsynk, upgraded over winter when the loads were higher and the production was down.  Great for overcast days as I don't even have to worry about switching the pool pump off most of the time. 

[Scubadude]

57 minutes ago, Sc00bs said:

I have 28 x 455w panels on 8kw Sunsynk, upgraded over winter when the loads were higher and the production was down.  Great for overcast days as I don't even have to worry about switching the pool pump off most of the time. 

That's a whole lot of panels! 12.74kWp ... the maximum input power of the 8kW Sunsynk / Deye is 10.4kW. Does the MPPT / charge controller throttle back production on good days?

At this stage my limiting factor most days is storage not production.  I will monitor carefully to decide whether to add a batery, a few more panels, or both, or nothing at all.  I'm worried I may not be able to get the same panels if that is the way to go and I wait too long.  

[hoohloc]

4 hours ago, Scubadude said:

That's a whole lot of panels! 12.74kWp ... the maximum input power of the 8kW Sunsynk / Deye is 10.4kW. Does the MPPT / charge controller throttle back production on good days?

At this stage my limiting factor most days is storage not production.  I will monitor carefully to decide whether to add a batery, a few more panels, or both, or nothing at all.  I'm worried I may not be able to get the same panels if that is the way to go and I wait too long.  

You can have as much panels as you want or can buy, but the inverter will only use what it is capable of using. I.e, if your inverter max PV input is 10.4kw and you have 20kw of PV, it will only use the 10.4kw it needs. The advantage of oversizing is that you have more to use in winter or on a cloudy/rainy days 

[Scubadude]

Thanks hoohloc ... been reading up on DC/AC ratios, inverter clipping, etc.  The decision to oversize or not would be so much easier if we had reasonable and fair feed-in tarrifs ... 11.4c/kWh simply isnt.

Back to my Solarman ramblings, with the help of Deye/Solarman support I got my Solarman Business account authorised and to make system changes on the web interface (Edge only ... for some reason Chrome wont show https://pro.solarmanpv.com/login). 

But still I could not get the app to do the same. It turns out version 1.5.6 on Google Playstore is over a year old. To get it working properly you have to download the latest apk (version 1.6.14) from https://www.solarman.cn/enterrace_3.html by scanning the QR code from your phone, then enable installation of unkown apps, and then install. 

EDIT: Doing the same for the Solarman Smart App enables the "Remote Control" button on the Device tab.  So the lesson is to always download the latest apk from Solarman, not from Google Playstore ... If I knew this before it would save me endless trouble.

EDIT 2: Now that my user has been enable to make system changes, I can also control the inverter remote on the Solarman Smart web interface. So if this is the only requirement there is no need to bother with Solarman Business at all .... 

Edited December 23, 2021 by Scubadude

[Sc00bs]

On 2021/12/22 at 9:08 AM, Scubadude said:

That's a whole lot of panels! 12.74kWp ... the maximum input power of the 8kW Sunsynk / Deye is 10.4kW. Does the MPPT / charge controller throttle back production on good days?

At this stage my limiting factor most days is storage not production.  I will monitor carefully to decide whether to add a batery, a few more panels, or both, or nothing at all.  I'm worried I may not be able to get the same panels if that is the way to go and I wait too long.  

Hi @Scubadude

My maximum power produced is 11.9kw, max daily production is 65.7kw/hr, will probably hit 70kw/hr+ if I had more storage available. As a result my average production is around 45kw/hr. Production on a clear day is usually throttled from about 11:00 by which time the batteries are usually fully charged. 

My average usage is 45-50kw/hr including my pool running for 8hrs @ 1kw. 

My pool switching is automated to only switch on for high forecast solar days only as such, if the forecast is for less than 40kw/hr it does not switch on in the morning. 

I have 12kw/hr of storage of which I have +-10kw/hr available with my 20% duty cycle. I use the battery after 22:00 at night and it is usually @ 20% by 06:00

According to my records, I have 13 days out of the last 90 days in which I have made less than than 30kw/hr of power and 9 days in which I made between 30-40kw/hr of power.  Going to be interesting to see how this compares in winter as there will be lower solar radiation but clearer sky's in Johannesburg so hopefully less days with less than 30kw/hr of production. My lowest production was 18kw/hr's.

I currently have enough battery power to get through load shedding and it doesn't really make sense financially for me to go more off-grid until the battery price comes down more. As such I use Eskom power from when the sun goes down until about 22:00 during which time we use 6-10kw/hr of power.

 

[Scubadude]

A quick update three weeks after going live properly ... despite the very wet and overcast conditions my solar fraction is above 80% on most days, and as high as 98% on a couple of days that we weren't home (only housesitter at home). Unfortunately two very low production (and high consumption) days dropped the overall solar fraction to 79%, so I am meeting my goal of 75% off-grid at this stage. Average savings R 55 per day and counting ... happy I am!

Quick question ... comparing Production + Purchased to Consumed shows 16kWh "went missing" during this period. That is about 3.8% of production. Does that mean my overall efficiency is 96.3%?

Edited January 12, 2022 by Scubadude

[Scubadude]

Very satisfying curves today ... battery either charging or discharging almost the entire day. I hate a flatlining battery - if it is not charging or discharging it is not saving me money.  23kWh generated despite a semi overcast day, and only 1.4kWh purchased. I couldnt have done it better if I flicked the geyser and pool switches myself!

[RabidBunny]

On 2021/11/28 at 2:03 AM, YellowTapemeasure said:

Why will it compromise yield on the majority of good solar days? That which does not get used on good solar days does not get generated. Yes, it's potential waste, but far better than watching production anxiously on a rainy day, wondering if you have enough light to charge batteries, and service loads, and whether the wife & kids will be able to have a warm bath tonight or tomorrow morning. It's days like this that can turn one into a nagging power nazi, constantly moaning at family members for making toast and using the microwave. 

I personally started out with 4.56kWp, and it was great, but I soon realised that life would be so much more comfortable with more. The MPPTs also far more efficient at higher voltages. Today my worst power output ever was at around 14H30. For about 10m I barely got 0.22kW out of my North-facing 26 degree 6.08kWp array. that's around 3.6%, and my batteries were at 65%. For me, it has absolutely nothing to do with "bragging rights". One installs what one is comfortable with, both in terms of usage and budget, in order to meet objectives. I am pretty sure that after one or two months you will come to a similar conclusion.

 

"It's days like this that can turn one into a nagging power nazi, constantly moaning at family members for making toast and using the microwave." ~ this was hilariously funny, yet true at the same time!

There should be a meme for this, "Let the Winter Games begin."

[Derek Ramos]

On 2021/12/22 at 8:06 AM, Sc00bs said:

I have 28 x 455w panels on 8kw Sunsynk, upgraded over winter when the loads were higher and the production was down.  Great for overcast days as I don't even have to worry about switching the pool pump off most of the time. 

@Sc00bsI’m a little confused by this, I thought that you had to stick by the Voc of the panel combined by the number of panels to give you a total volatage. So the 8kw sunsynk has a max DC input voltage of 500v per mppt. So I can fit 10x 545watt panels at a 49,52voc to make 495,2v Per mppt. Is this correct? I checked some 455watt panels and it seems the Voc is almost the same as the 545watt. Won’t this damage your inverter. Assuming you have 14 panels per string at 49voc then that would give you 686v. 

[Sc00bs]

Hi @Derek Ramos 

You are 100% correct, if you put them all in series your voltage will be way to high and you would damage your MPPT controllers. 

I have 12 Panels on one string 6Series2Parallel & 16 Panels on my other string 8S2P 

Specs on the panels are 

• Open Circuit Voltage (Voc): 49.85 V
• Short Circuit Voltage (Isc): 11.41 A

So max should be about 22A & 300V on the 6S & 400V on the 8S strings.

The inverter will handle up to 18A after which it will throttle the amps by increasing the resistance in the inverter. This only really happens on high power production days and I am only loosing a few amps at the top of the range when I already have more power than I know what to do with. I does however ensure maximum production on more marginal days.

After cables etc voltage on the string is, on the 6S2P - +- 250V  & 8S2P  +-325V (slightly longer cables resulting in slightly lower voltage)

I hope that gives you a better idea of how I have mine setup. 

 

[Derek Ramos]

2 hours ago, Sc00bs said:

Hi @Derek Ramos 

You are 100% correct, if you put them all in series your voltage will be way to high and you would damage your MPPT controllers. 

I have 12 Panels on one string 6Series2Parallel & 16 Panels on my other string 8S2P 

Specs on the panels are 

• Open Circuit Voltage (Voc): 49.85 V
• Short Circuit Voltage (Isc): 11.41 A

So max should be about 22A & 300V on the 6S & 400V on the 8S strings.

The inverter will handle up to 18A after which it will throttle the amps by increasing the resistance in the inverter. This only really happens on high power production days and I am only loosing a few amps at the top of the range when I already have more power than I know what to do with. I does however ensure maximum production on more marginal days.

After cables etc voltage on the string is, on the 6S2P - +- 250V  & 8S2P  +-325V (slightly longer cables resulting in slightly lower voltage)

I hope that gives you a better idea of how I have mine setup. 

 

Yes this helps, thank you for the explanation