MPPT controller only working in PWM mode

[DorisTheVengeful]

I've a Ooycyoo MPPT30 controller, or so I reckon, it was second hand. I'll include a pic:



It would be great if anyone out there actually owned one of these - or even had access to a manual, although the manuals I've found for different Ooycyoo models haven't been particularly informative - and could tell me if my experience is normal. I'm new to all this so can anyone explain why the display says 'controller PWM' above 12 point whatever Volts? Shouldn't it say MPPT when charging?

Unless my model is PWM and not MPPT after all - even though it says MPPT30 in big red letters on the case I'm not entirely discounting this possibility - then either there's something wrong with my (second hand) controller or I'm doing something wrong. Assuming the latter my setup is pretty simple: a 280W panel and a 12V leisure battery. It seems I can't upload a video of my setup charging without compressing it but here's a pic of my setup charging at 300 odd mA but still showing PWM!

Anyone know what's going on here? Or have any tips on settings or on how to diagnose the problem?
Thanks for reading all this blah!
Regards

 

[Backyard]

I doubt it's actually an MPPT charger. Many of those cheaper "MPPT" chargers are in fact PWM. They put MPPT on the lable for marketing purposes

Open it up and take a picture and we can for sure tell if it's MPPT or PWM

 

[v_green57]

When PV voltage is only a couple volts higher than battery voltage (as your images suggest), there isn't enough input for MPPT to work with and many MPPT controllers run in "passthrough", which is PWM.

Why is your PV input so low, and why does the display say PV OFF? Do you ever get any decent power (> 300 mA) to the battery?

This thing may be borked.

 

[Minimoose]

I've a Ooycyoo MPPT30 controller, or so I reckon, it was second hand. I'll include a pic:

View attachment 285260

It would be great if anyone out there actually owned one of these - or even had access to a manual, although the manuals I've found for different Ooycyoo models haven't been particularly informative - and could tell me if my experience is normal. I'm new to all this so can anyone explain why the display says 'controller PWM' above 12 point whatever Volts? Shouldn't it say MPPT when charging?

Unless my model is PWM and not MPPT after all - even though it says MPPT30 in big red letters on the case I'm not entirely discounting this possibility - then either there's something wrong with my (second hand) controller or I'm doing something wrong. Assuming the latter my setup is pretty simple: a 280W panel and a 12V leisure battery. It seems I can't upload a video of my setup charging without compressing it but here's a pic of my setup charging at 300 odd mA but still showing PWM!
View attachment 285298
Anyone know what's going on here? Or have any tips on settings or on how to diagnose the problem?
Thanks for reading all this blah!
Regards

I found it on ebay. Looks like it's a PWM from the pictures.

 

[Sabre36]

I found it on ebay. Looks like it's a PWM from the pictures.
View attachment 285331View attachment 285330

That’s not an MPPT…

 

[Rednecktek]

The USB port is a dead giveaway.

 

[AshleyL]

If it is an MPPT controller, then where is the inductor? I don't see any inductor from the picture.

 

[time2roll]

Do you have a 24+ volt panel to connect to a 12v battery?

 

[DorisTheVengeful]

Thanks for all the replies guys. Although my original query is answered - ie. it's  not an MPPT controller, I've ended up with more questions. But this is how we learn, by exposing gaps in ones knowledge we go from a state of ignorance to one of, if not expertise, at least competence. Blah, blah... I'm not at all au fait with forums so apologies if I'm doing this all wrong but here goes:

I doubt it's actually an MPPT charger. Many of those cheaper "MPPT" chargers are in fact PWM. They put MPPT on the lable for marketing purposes

Open it up and take a picture and we can for sure tell if it's MPPT or PWM

Minimoose has been kind enough to sort this one for me:

I found it on ebay. Looks like it's a PWM from the pictures.
View attachment 285331View attachment 285330

So, not an MPPT. But what am I looking for here? What should I see / not see with an MPPT controller? An inductor?

If it is an MPPT controller, then where is the inductor? I don't see any inductor from the picture.

From what I remember of my long ago electronics studies an inductor is a curly bit of wire. The lack of an inductor indicates that it's not an MPPT controller? And...

The USB port is a dead giveaway.

Do MPPT controllers not have USB ports? I mean do MPPT controllers not generally have USB ports or is there something about MPPT controllers that precludes them from having USB?

As to what v_green57 says:

When PV voltage is only a couple volts higher than battery voltage (as your images suggest), there isn't enough input for MPPT to work with and many MPPT controllers run in "passthrough", which is PWM.

Why is your PV input so low, and why does the display say PV OFF? Do you ever get any decent power (> 300 mA) to the battery?

This thing may be borked.

I'd guess the input is so low mainly because of the glorious British weather. I've only had my setup for around a week and it's been continuously overcast since. I don't know why it says PV off. Could it be because my settings are out? Actually, I'm not even sure that the PV-A reading is correct. It's overcast right now and although the flashing arrows indicate charging, actually measuring the current flow with my multimeter gives around 200-300mA but the display reads zero and PV off.
The settings I can adjust are Load off-V, Load on-V and PV off-A. Do I have these settings near to correct? What would be the ideal settings for a single 280W panel and a single 12V, 115Ah leisure battery? I don't really understand these settings. If someone could give a brief explanation of each it would be greatly appreciated. Many thanks to all

 

[rodrick]

Do MPPT controllers not have USB ports? I mean do MPPT controllers not generally have USB ports

Correct those with the usb ports are the typical $6-12 range eBay pwm units and they mis lead the consumer with mppt as brand name or something

 

[mikefitz]

Ooycyoo MPPT30 controller,

Not MPPT , perhaps broken. You may be able to set the charge voltage.
To set up the charge voltage go through the settings with the left button until you see 'PV off ' or similar term, hold the button down until the value starts to flash. Use up/ down buttons to set the charge volts, say 14.4 volts. Press right button to accept value.
Even when new these controllers did not work very well. Suggest you buy a real MPPT controller. You need a 20 amp unit, recomended Victron Smart 100/20.

should I see / not see with an MPPT controller? An inductor?

A MPPT controller is an energy converter that requires an intermediate energy store in the conversion process. The inductor stores magnetic energy.

Do MPPT controllers not have USB ports?

Irrelevant to the purpose of a solar controller. Low cost PWM controllers often add USB to offer 'value'.

.What would be the ideal settings for a single 280W panel and a single 12V, 115Ah leisure battery? I

As sugested above PV off is the voltage up to which the battery charges before the controller turns off the PV power. So PV off is the charge voltage, set to 14.4.
You solar panel will have a specification on the rear showing I max power, it will be either in the region of 8 amps or 15 amps depending on the panel voltage. This current is the maximum the controller will put into the battery .

 

[DorisTheVengeful]

Thanks for your complete and concise response but I've a few more questions if that's OK.

So PV off is the charge voltage, set to 14.4.

So, I reckon I get the PV off - the battery reaches 14.4V and the panel is switched off so the battery doesn't bubble away and fry.
Not entirely sure I understand the Load on/off settings though - is this to do with what I've connected to the load terminals, some LED lights or whatever? And the settings are the battery Voltage at which the lights would turn on or off?
But my main questions are to do with the controller you recommended.

Suggest you buy a real MPPT controller. You need a 20 amp unit, recomended Victron Smart 100/20.

I assume you've owned one of this range so can tell me if I'll be able to monitor/adjust the controller via Bluetooth? Do I have to be sure to buy a particular model or some peripheral device? Also, I may have access to a couple of 100W panels. The total Imp of all panels is 19.63. As this is max current, is 20A enough, or is it best to have more of a safety margin?
And can anyone point me to some independent figures on the efficiency of MPPT compared to PWM?

 

[mikefitz]

battery reaches 14.4V and the panel is switched off

Not so much switched off completly, but switched on and off to hold the average volts at 14.4, this is pulse width modulation , PWM.

Load on/off settings

You may have the possibility to switch on the load when it gets dark, controlling remote lighting, and/or disconnected the load outpiuts from the battery, if the battery volts get too low.

to monitor/adjust the controller via Bluetooth

Yes with the Smart version.
With a 280 watt panel and a 12v 115Ah battery, ( assume a sealed lead acid battery) you need a 20 amps unit. The current rating is panel power/ battery charge volts, 280/14.4 = 19.4 amps. The various Victron models are designated by two numbers, example 100/20. 100 is the maximum panel volts and 20 is the maximum output current.
What panels will you be using, two 100 watt or one 280 watt, or all three?

have more of a safety margin?

You can always have a controller with a higher rating. Experience Indicates that Victron controllers can operate reliably at full rated current. If you add more panels to the system at some stage , adding an additional controller is no problem, you can have a number of controllers feeding the same battery pack.

independent figures on the efficiency of MPPT compared to PWM?

It's quite simple. A panel will have a maximum power voltage and current, the MPPT controller loads the panel for maximum power and converts this power to a suitable voltage and current for the battery. A PWM controller just transfers the maximum current to the battery.
Example, a JX280M 280 watt panel has I max power =10.7A , V max power 26 volts. Assume the battery is charging at 14.4 volts.
MPPT current into the battery, 10.7 * 26 / 14.4 = 19.3 amps. Power into the battery, 19.3 * 14.4 = 278 watt
PWM current into the battery, 10.7 amps. Power into the battery 10.7 * 14.4 = 154 watts.

Note you have a 115 Ah lead battery, recomended charge current maximum 15 to 20 amps.

 

[DorisTheVengeful]

Thanks for another comprehensive answer.

What panels will you be using, two 100 watt or one 280 watt, or all three?

To clarify, I'm currently using one 250W (not 280W, someone who wasn't wearing there glasses had, with a marker pen, written 280W in large friendly letters.) Also I  may have access to 2 x 100W panels. They belong to one of my neighbours but as she's suffering from depression none of us see as much of her as we'd like. We're a tight knit bunch but it can be so debilitating that when you can't even prise someone out their gaff what can you do... Anyway, excuse the digression... The 2x100W panels have been sat outside for a couple of years or so, lent against her (old) truck PV side shaded so I'm guessing all will be fine.
But as I'm on a limited budget there are future considerations; I can afford a 20A version or even a 30A one at a pinch, though I'm not sure 30A model would be of much use to me. Though your calculations have made it plain that MPPT is much more efficient than PWM perhaps you'd be so kind as to check my maths? To make sure I'm buying correct controllers, that is:
The 250W panel: 250W/14.4V = 17.36A
The 100W panel: 100W/14.4V = 6.94A
2 x 100W panels = 13.89A

So, even adding a single 100W panel to the suggested 20A Victron controller would be over 20A (17.36A + 6.94A > 20A)
And buying a 30A controller wouldn't quite make it for 250W + 2 x 100W panels (17.63A + 13.89A > 30A) If I'm understanding things correctly I can put my 250W panel through one 20A controller and the two 100W panels through a different 20A controller and attach the outputs of each to a single battery bank?
And if you can endure answering just one more thing:

a 12v 115Ah battery, ( assume a sealed lead acid battery) you need a 20 amps unit.

Note you have a 115 Ah lead battery, recomended charge current maximum 15 to 20 amps.

If I am to eventually add more panels, it looks like a 115Ah lead acid battery won't cut it. Could you tell me how 'recomended charge current maximum' is calculated and perhaps advice me on the different types of battery available, those generally used in Solar power collection that is. Or point me to where I should be looking for such information. Many thanks

 

[mikefitz]

like a 115Ah lead acid battery won't cut it

Before making any suggestions on how to proceed and what stuff to buy, what is the plan?
Looking back at your posts you said ,
'All my electricity needs are to keep my phone charged, use a laptop, and some LED lights. To this end I've acquired a 280W PV solar panel, an 'Ooycyoo mppt30' controller, an 115Ah leisure battery and an 150W inverter'
Although expensive compared to a PWM controller a resionable MPPT has advantages, more power from a panel, gives useful information on the charge process, can limit the battery charge current. But solar power is minimal on cloudy dull rain conditions and winter short daylight time limits yield.
I suggest buying a Victron 100/20 smart controller,

Victron Energy SmartSolar MPPT Charge Controller 100/20

Victron Smart Solar 100/20 MPPT Charge Controller with Bluetooth built-in. For 12V & 24V systems in motorhomes, caravans, campervans & boats.

www.12voltplanet.co.uk

Using the Bluetooth app gives assess to the chargers daily performance and instant battery voltage and charge current. This helps manage power and will give you a useful learning period.
The battery is OK for now, once you have some data you can decide if it's worth investing on additional or different battery types
With a MPPT controller you can 'over panel', it just limits the current at the design limit. This gives you useful power in poor solar conditions. The limit with the recomended controller is 100 volts maximum panel, 20 amps current.
Panels can be connected in parallel if they have similar voltages, and in series if they have similar currents.

My guess for your modest requirements is that the 250 watt panel and a single battery will be OK , apart from mid winter and a sequence of poor solar days.
Do you have alternative power, AC mains supply, a vehicle or a portable petrol generator?

 

[DorisTheVengeful]

I'm waiting for suggested Victron controller to arrive in post (tonight or tomorrow) and will be able to supply better charging etc info.

Do you have alternative power, AC mains supply, a vehicle or a portable petrol generator?

No mains, I've a portable 'suitcase' generator but it's unreliable, never know if it going to run. I do have a van but having trouble getting it running. Can't be much wrong with it but my head is not in right place for vehicle work just now. Soon though, as I seem to have been promising myself for a year or so!

 

[Lorre]

I'm waiting for suggested Victron controller to arrive in post (tonight or tomorrow) and will be able to supply better charging etc info.



No mains, I've a portable 'suitcase' generator but it's unreliable, never know if it going to run. I do have a van but having trouble getting it running. Can't be much wrong with it but my head is not in right place for vehicle work just now. Soon though, as I seem to have been promising myself for a year or so!

Be sure to use the right size electrical cables. That's important for efficiency as well as safety.

 

[DorisTheVengeful]

Indeed. As we live along a track with a wooded hill on one side and a steep river bank on tother (just, one or two trees.) Anyways, all this rather pointless biographical info is to say there's a gap in the trees, opposite my neighbours van, where there was once a bridge or something. So my panels are 25ish metres away. The cables are looking to be the most expensive parts of my setup!
Finally, this what I wanted your opinion on. I've some cable I estimate to be about 2-2.5mm². It's at least twice the necessary length so what do think if I were to chop it two and join it together again, but in parallel so to speak. That is, join blue to blue at each end and the same with the brown ends?
Also, as it's three core cable, what do you reckon to joining the neutral to one or other of the wires? Would this give me a performance increase or just use the highest resistance wire? From my long ago physics studies I seem to remember a formula adding up resistors in parallel but dunno if it counts here.
Any info much appreciated!

 

[Rednecktek]

You're talking about using multiple smaller conductors to provide more copper between point A and point B rather than having to run a single fat wire? Yup, works just fine and we do it all the time on heavy movers on ships. As long as each conductor can take over half the amperage and the wires are the same length, the load imbalance to resistance is pretty negligible. In short, go for it.

 

[Glock24]

The USB port is a dead giveaway.

Usually yes but there are some legit MPPT controllers with USB ports, like the EcoBoost MPPT line from Morningstar.

 

[DorisTheVengeful]

You're talking about using multiple smaller conductors to provide more copper between point A and point B rather than having to run a single fat wire? Yup, works just fine and we do it all the time on heavy movers on ships. As long as each conductor can take over half the amperage and the wires are the same length, the load imbalance to resistance is pretty negligible. In short, go for it.

Right. Remembered (looked up) parallel resister formula: Rt = Ra + Rb + Rc...

"As long as each conductor can take over half the amperage..."

If I'm understanding correctly, joining 2 wires would be R/2 and joining 3 wires would be R/3 so is fine with the above quote. It'd only start to be a problem if I joined 2 wires (or even 3) and for some reason only used 1 wire for other polarity. I assume i can add more copper of a different gauge, if they're roughly the same length and i don't do anything mental like adding 3 cores to the + and nothing to the -.
Q. Does it make any difference which polarity has the greater or lesser current?
Thanks

 

[Lorre]

Right. Remembered (looked up) parallel resister formula: Rt = Ra + Rb + Rc...

"As long as each conductor can take over half the amperage..."

If I'm understanding correctly, joining 2 wires would be R/2 and joining 3 wires would be R/3 so is fine with the above quote. It'd only start to be a problem if I joined 2 wires (or even 3) and for some reason only used 1 wire for other polarity. I assume i can add more copper of a different gauge, if they're roughly the same length and i don't do anything mental like adding 3 cores to the + and nothing to the -.
Q. Does it make any difference which polarity has the greater or lesser current?
Thanks

Not roughly the same length.. Every wire has to be exactly the same length in the DC circuit: from the solar panels, between the solar panels to the charge controller, to the battery to the inverter. Every positive wire must be the same length as it's negative counterpart. The thickness (guage) must also be the same to avoid imbalances and other gremlins from sneaking in.

 

[pollenface]

If you add a buck converter between the panel and the pv input of a pwm set to 14.6v it will yield more charging current.

Maybe 15v if temperature compensation is used.

 

[Recovering EE]

Unscrupulous vendors on Amazon and EBay and the like will take cheap Chinese PWM controllers, and rebrand them. Sometimes they'll make the company name have "MPPT" in it, or create a model number with "MPPT" in it, and plaster that all over the product case, even though it's a PWM controller. They hope to fool the consumer into thinking it's an MPPT controller, sell a couple hundred of them, ignore the returns and trouble calls, go out of business, create a new company name and model number (with MPPT" in both), and start all over.

Consumer fraud is their business model, and the Chinese government doesn't give a rat's a$$, because they're still bringing in those sweet US dollars.

 

[Backyard]

Not roughly the same length.. Every wire has to be exactly the same length in the DC circuit: from the solar panels, between the solar panels to the charge controller, to the battery to the inverter. Every positive wire must be the same length as it's negative counterpart. The thickness (guage) must also be the same to avoid imbalances and other gremlins from sneaking in.

This is incorrect