Switched from PWM to MPPT, now can't use all panels, controller goes to sleep when I exceed 800 watts

[Sabi]

I have 1240 watt in solar panels.
Up til now I had 720 Watts (sitting on the ground) connected in parallel via two 30A PWM controllers to a battery bank of four 100 Ah batteries and two 100 watt panels on the roof through an additional 30A PWM controller connected to the batteries. The 2 roof panels are now under shade cloth (90% shade 100% UV protection), so they are not doing much.
I recently added panels and changed to MPPT controllers and I now have a problem.
I have two 300 Watt panels going into one 60A MPPT controller, and that one is working fine.
I hooked up two 200 watt panels into a second 60A MPPT controller and that one goes to sleep mode.
When I unplug one of the 200 watt panels (for a total of 800 watts), the second controller goes to charge mode.
Adding anything does not work.
I added the second 200 W panel with a 3rd 60A MPPT controller, and the 3rd one goes to sleep mode; the others remain charging.
I added a 240 W panel instead of the 200 W panel to the second 60A MPPT controller and it goes into sleep mode.
It seems adding anything over 800 watts doesn't work.
I was thinking maybe the four 100Ah batteries can only handle 200 W each, but that doesn't make sense as I want to use some juice during the day, not store everything.
My goal with the upgrade (planning on 1500 W) was to have enough solar to run a small window AC during the day (should take around 1000W) and have some power put into the batteries to have power for overnight.
The 60A MPPT controllers are from a company called Werchtay where tech support doesn't speak english and the sales rep was no help.
Is it possible that the batteries can limit what imput in watts the MPPT Controller allows?
Do I need a different MPPT controller or should I go back to PWM. I know the MPPT controllers are supposed to be UP to 30% more efficient but I'm leaving more than that on the table with the panels I can't use.
I would appreciate any suggestions.
Thank you very much.

 

[yodamota]

maybe try swapping the charge controllers. I have never heard of werchtay. https://www.amazon.com/WERCHTAY-Controller-Tracking-Regulator-Multiple/dp/B09XF1S3W1 Wow those cost 26 bucks!!! no wonder you are having problems! Try using a quality charge controller.

What about using a victron/morningstar/outback power charge controller?

 

[mikefitz]

Do I need a different MPPT controller or should I go back to PWM. I know the MPPT controllers are supposed to be UP to 30% more efficient but I'm leaving more than that on the table

You new controller is PWM, false advertised as MPPT.

A true MPPT controller will cost a great deal more than $26.

https://www.amazon.com/Controller-Negative-Grounding-Suitable-Monitoring/dp/B07KB4G4WD/ref=sr_1_2_sspa?crid=2MHD2ESI9P70J&keywords=60%2Bamp%2Bsolar%2Bcontroller&qid=1690963251&sprefix=60%2Bamp%2Bsolar%2Bcontro.ler%2Caps%2C201&sr=8-2-spons&sp_csd=d2lkZ2V0TmFtZT1zcF9hdGY&th=1

https://www.amazon.com/Victron-SmartSolar-Charge-Controller-150V/dp/B07B4KF7LY/ref=sr_1_3?crid=2UXW2AMWECP47&keywords=victron+60+amp+solar+controller&qid=1690963353&sprefix=victron+60+amp+solar+contro.ler%2Caps%2C175&sr=8-3

1500 watts of solar needs a MPPT rated at 120 amps, or two at 60 amps. In a 12v system.
It seems that your panels are all connected in parallel. With a MPPT controller higher input voltages can be used, thus allowing series strings of panels to be used.

 

[Sabi]

maybe try swapping the charge controllers. I have never heard of werchtay. https://www.amazon.com/WERCHTAY-Controller-Tracking-Regulator-Multiple/dp/B09XF1S3W1 Wow those cost 26 bucks!!! no wonder you are having problems! Try using a quality charge controller.

What about using a victron/morningstar/outback power charge controller?

Thank you.

 

[Sabi]

You new controller is PWM, false advertised as MPPT.

A true MPPT controller will cost a great deal more than $26.

https://www.amazon.com/Controller-Negative-Grounding-Suitable-Monitoring/dp/B07KB4G4WD/ref=sr_1_2_sspa?crid=2MHD2ESI9P70J&keywords=60%2Bamp%2Bsolar%2Bcontroller&qid=1690963251&sprefix=60%2Bamp%2Bsolar%2Bcontro.ler%2Caps%2C201&sr=8-2-spons&sp_csd=d2lkZ2V0TmFtZT1zcF9hdGY&th=1

https://www.amazon.com/Victron-SmartSolar-Charge-Controller-150V/dp/B07B4KF7LY/ref=sr_1_3?crid=2UXW2AMWECP47&keywords=victron+60+amp+solar+controller&qid=1690963353&sprefix=victron+60+amp+solar+contro.ler%2Caps%2C175&sr=8-3

1500 watts of solar needs a MPPT rated at 120 amps, or two at 60 amps. In a 12v system.
It seems that your panels are all connected in parallel. With a MPPT controller higher input voltages can be used, thus allowing series strings of panels to be used.

Wow, that is really interesting. But if it is actually a PWM, shouldn't they work together in parallel as my old 30A PWMs did? The part that still puzzles me is that they do 800 watts but nothing above 800 watts.

 

[Sabi]

Thank you so much for your replies, that is very helpful. I think you're right, I need to toss those 28$ MPPT controllers, I have been wondering why some cost 30$ and others cost 400$.
But I'm thinking I need to figure out first why I can't get over 800 Watts, why the go to sleep when I go over. Or maybe it is because they are crap controllers. With my old 30A PWMs - 2 of them - I ran 720 watts no problem.
I had just talked to Renogy to see what they have, and the salesperson was thinking that I should disconnect the old Renogy 30A Adventurer controller because their's are not designed to mix with anything (they did work fine with my other PWMs). But I figure it can't hurt to disconnect them as the panels attached to them are now shaded.
Which brand MPPT controllers do you have, and do you have any feedback on whether they come with reachable tech support?
I am also curious if it would be better to go with 2 60A controllers (the 60A renogy rover does 800w) or one 100A controller (the 100A renogy rover handles 1300 watts).
I've also been told that maybe the fact that my panels have different wattage could be a problem, and that I should have the two 300 watt panels go into one controller and the two 200 watt and one 240 watt panels should go into another. The renogy sales rep seemed to think they can all go into the rover 100. Curious about your experiences.
And one other loaded question: with solar panels having gotten sooo cheap, is it worth to fork out a ton of money for an expensive MPPT controller, or more cost-effective to have a bunch of PWMs with more solar panels?

 

[Pappion]

MPPT my need a higher voltage overhead. Amazon reviews claim these will destroy batteries and not for lithium. 14% 1 star reviews. Stay away.

Victron Smart Solar Charge Controllers blue tooth network together. 1st one up controls the other and places them in the same charge mode; bulk, absorption, float etc.. This prevents the late starters being in the wrong mode due to 1st ones voltage.

BTW: I had a cheap MPPT. It was only MPPT during Bulk and would Bulk every morning whether the batteries needed it or not. My batteries were boiling, the voltage was high. I tried to trim the voltage by trimming the temperature sensor resistance. It trimmed Float Voltage but had no effect on Bulk/Absorption Voltage.

 

[schmism]

I am also curious if it would be better to go with 2 60A controllers (the 60A renogy rover does 800w) or one 100A controller (the 100A renogy rover handles 1300 watts).

2 60A renogy controlers is like $600. For the same money you could have bought a single import AIO and gained the inverter for free!

 

[ericfx1984]

So yeah this is not actually an MPPT charge controller... They advertise it as such but it's false advertising it's been going on forever

2 60A renogy controlers is like $600. For the same money you could have bought a single import AIO and gained the inverter for free!

 

[Rednecktek]

HQST, Epever, Rich Solar, even Renogy would be viable options. Even PowMr would still turn solar DC into battery DC and be better than what your PWM's can do. Hell, a 50a Sunthsys is only about $100

Do everything you can to avoid mixing and matching panels as the entire string will be nerfed to the lowest common panel voltage and amperage. I.E. if you had 6 350w panels and a 100w panel, you'd get nerfed to 700w.

It sounds a lot like a voltage setting. If the first controller is set to charge at 14.6v and the second wants to charge at 14.4v, the second SCC could be seeing the 14.6 on the wire and thinking the battery is full, no need to charge, go to sleep.

 

[ericfx1984]

HQST, Epever, Rich Solar, even Renogy would be viable options. Even PowMr would still turn solar DC into battery DC and be better than what your PWM's can do. Hell, a 50a Sunthsys is only about $100

Do everything you can to avoid mixing and matching panels as the entire string will be nerfed to the lowest common panel voltage and amperage. I.E. if you had 6 350w panels and a 100w panel, you'd get nerfed to 700w.

It sounds a lot like a voltage setting. If the first controller is set to charge at 14.6v and the second wants to charge at 14.4v, the second SCC could be seeing the 14.6 on the wire and thinking the battery is full, no need to charge, go to sleep.

I wouldn't use the PowMR... I had really bad luck with the first two that I tested

 

[Rednecktek]

I wouldn't use the PowMR... I had really bad luck with the first two that I tested

I've got 2 of the old metal ones going strong after 5 years. Never really pushed them to capacity but they still turn solar DC into battery DC and are better than the "MPPT Controller" shown above.

At the time I was on a budget and they were 60a for $100ea compared to the $350+ for an EPEver or Rich Solar. I had cats to feed after all. ?

 

[ericfx1984]

I've got 2 of the old metal ones going strong after 5 years. Never really pushed them to capacity but they still turn solar DC into battery DC and are better than the "MPPT Controller" shown above.

At the time I was on a budget and they were 60a for $100ea compared to the $350+ for an EPEver or Rich Solar. I had cats to feed after all. ?

A 60 amp EP ever is about $250

But you're right you can get these for about $100

I bought a pair of them a while back One of them had two screws just flopping around inside the unit I replaced those and I fired both of them up... What I found was they could only handle about 60 or 70 volts PV on a 12 volt nominal battery

Additionally they ran hot... Like hot enough that if you touch them it was uncomfortable

I can tell you none of my EP evers run that hot... And my Victron doesn't run that hot

Worse yet The PowMR had a smell very similar to burning plastic

It would shut down sometimes because of heat, or I should say both of them would shut down sometimes due to heat

I can tell you my EP evers can handle 130v of PV going into a 12 volt nominal battery... And that made it way more affordable to wire all this up

 

[Rednecktek]

Hands down an EPEver or HQST is going to be a better quality controller and should definitely be considered if budget allows.