you get small mppt chargers for ~20$ pwn you get for ~10$ i will ever touch a pwm coz the prize diff is not really there. and its not 16% mppt is DC to DC convert. if you have a panel with 28 Volts and your battery is a 13 volt one then the dc to dc convert doubles the Amperes for example. mppt = convert near all power from panel into usefull current for your battery. pwn= on off switch so AMps are still untouched or reduzed about switching on and off....
I understand the basics of both systems but i noticed that my (more expensive) MPPT conroller has a self-usage that is draining the battery when there is no sun. It just depletes a 30Ah 12v Lead acid battery overnight by as much as a full volt. I mean that is the amount i gathered on a cloudy day. If you have several Kwh in battery capacity i see there is a minimal drop but with a small 30Ah battery it makes no sense using a MPPT like that. Mine has no menu option to disable output load. So it basically is always converting battery power to 12v. No USB is on my MPPT unit also. So be aware what you charge and what remains overnight of that gain with small batteries and mediocre sun. -- In retrospect i also have a 30 Watt panel and a cheap Solar Generator charging rather quickly with it and has electronics to remain at 100% charge for a very long (shelf) life. I mean, why can't they make it like that in more expensive MPPT charge controller. I am really disapointed in these big and expensive MPPT units.
Now, that's a perspective not commonly seen, but makes a lot of sense! We tend to debate continuously. About which system produces more! In fact I believe it's the first time I see someone exposing how much the system can "leak"! I do believe I noticed similar on some of my small systems, but quite honestly never bothered to the point of checking it. I guess now I'll have a closer look! Awesome point to keep in mind. Cheers
It is an unfortunate behaviour of a charge controller if it depletes the battery overnight. I'm interested in this phenomenon because I wouldn't like this to happen when I build my first off-grid system. But I've read an opinion that nowadays most mppt controllers have a diode that blocks backward current to prevent this from happening. I'm wondering how common that is.
Now I've been using EPEVER XTRA 20A for more than a month and when there is no sun it draws 23mA from the battery, which I consider small enough not to be a problem. But by default the load output is turned on and then the power draw is twice as much but I can turn it off and it drops to 23mA. When the LCD is lit it adds 7mA. It looks like there is no backward current from the battery to the panels but the charge controller needs some small amount of power for its operation. But I understand this may vary a lot between different charge controllers.
i find mppt come in to there own when you get the cheaper grid tie higher voltage solar panels when people are replacing them or overstock and run a 12v battery system
I think that an mppt is making sense when having higher voltage panel, like 37V ones. I made a simple, small, 12V system with two 250w panels (one facing east and the other one SE) since these were the cheapest SH ones in my country :) and an 20A mppt solar charge controller and I think it's a great deal while using these higher voltage pv panels. While I hooked up the panels in parallel(so that the solar generation would not drop too much if one of the panels is shaded) most of the time I see my mppt doubles the Amps from the panels into the battery. I think that the cheap pwm controllers would not even work with a 12v battery, having 30+ volts pv panel input. Nice video!
With PWM just about any voltage over your battery voltage is LOST. It'll work with 30v on pwm and a 12v battery but you'll lose the 18v of power. PWM is the Fisher Price of charge controllers, fine for a panel or two at 12v maybe but def not very efficient. Be aware of "MPPT" controllers that aren't. China likes to scam people with these. If it doesn't have an induction coil in it then it's not an MPPT.
For foldable 120w panels, output being 18v DC would a MPPT be better? I have a GZ yeti which has built in PWM, however it can take I out from Anderson connections so I could put a MPPT into there
If you're system is 12v, you're fine with pwm, there is not that big of difference but when your system is 18v or higher, it is better to use mppt to maximize the output of your system, getting all that extra juice from the excess voltage and converting them into amps, in turns higher efficiency 😉
How do you deal with the mppt not starting until Vbat+5 ? My panel is 16.5V in the sun which means it won't trigger the mllt charging until the battery is below 50%
MPPT has gotten a lot cheaper no reason to go with PWM. RV industry is still installing PWM controllers I don't know why on a small trailer with one deep cycle lead acid you need every amp you can get if your camping for extended days.
A 16% improvement was more than I was expecting. Thanks for the video, it was eye opening
you get small mppt chargers for ~20$ pwn you get for ~10$ i will ever touch a pwm coz the prize diff is not really there.
and its not 16% mppt is DC to DC convert.
if you have a panel with 28 Volts and your battery is a 13 volt one then the dc to dc convert doubles the Amperes for example.
mppt = convert near all power from panel into usefull current for your battery.
pwn= on off switch so AMps are still untouched or reduzed about switching on and off....
Short and to the point. Fantastic. I subscribed.
Thank you for your kind words.
First thing I did was change from the $2.00 PWM controller to a Victron MPPT.
I understand the basics of both systems but i noticed that my (more expensive) MPPT conroller has a self-usage that is draining the battery when there is no sun. It just depletes a 30Ah 12v Lead acid battery overnight by as much as a full volt. I mean that is the amount i gathered on a cloudy day. If you have several Kwh in battery capacity i see there is a minimal drop but with a small 30Ah battery it makes no sense using a MPPT like that. Mine has no menu option to disable output load. So it basically is always converting battery power to 12v. No USB is on my MPPT unit also. So be aware what you charge and what remains overnight of that gain with small batteries and mediocre sun. -- In retrospect i also have a 30 Watt panel and a cheap Solar Generator charging rather quickly with it and has electronics to remain at 100% charge for a very long (shelf) life. I mean, why can't they make it like that in more expensive MPPT charge controller. I am really disapointed in these big and expensive MPPT units.
Now, that's a perspective not commonly seen, but makes a lot of sense! We tend to debate continuously. About which system produces more! In fact I believe it's the first time I see someone exposing how much the system can "leak"! I do believe I noticed similar on some of my small systems, but quite honestly never bothered to the point of checking it. I guess now I'll have a closer look!
Awesome point to keep in mind.
Cheers
It is an unfortunate behaviour of a charge controller if it depletes the battery overnight. I'm interested in this phenomenon because I wouldn't like this to happen when I build my first off-grid system. But I've read an opinion that nowadays most mppt controllers have a diode that blocks backward current to prevent this from happening. I'm wondering how common that is.
Now I've been using EPEVER XTRA 20A for more than a month and when there is no sun it draws 23mA from the battery, which I consider small enough not to be a problem. But by default the load output is turned on and then the power draw is twice as much but I can turn it off and it drops to 23mA. When the LCD is lit it adds 7mA. It looks like there is no backward current from the battery to the panels but the charge controller needs some small amount of power for its operation. But I understand this may vary a lot between different charge controllers.
i find mppt come in to there own when you get the cheaper grid tie higher voltage solar panels when people are replacing them or overstock and run a 12v battery system
I think that an mppt is making sense when having higher voltage panel, like 37V ones. I made a simple, small, 12V system with two 250w panels (one facing east and the other one SE) since these were the cheapest SH ones in my country :) and an 20A mppt solar charge controller and I think it's a great deal while using these higher voltage pv panels.
While I hooked up the panels in parallel(so that the solar generation would not drop too much if one of the panels is shaded) most of the time I see my mppt doubles the Amps from the panels into the battery.
I think that the cheap pwm controllers would not even work with a 12v battery, having 30+ volts pv panel input.
Nice video!
Thank you, made this video before my bigger Sony camera.. But hopefully it still looks ok and I got the information across.
Good quality video, and very useful information. 👍
With PWM just about any voltage over your battery voltage is LOST. It'll work with 30v on pwm and a 12v battery but you'll lose the 18v of power. PWM is the Fisher Price of charge controllers, fine for a panel or two at 12v maybe but def not very efficient. Be aware of "MPPT" controllers that aren't. China likes to scam people with these. If it doesn't have an induction coil in it then it's not an MPPT.
Good info.
For foldable 120w panels, output being 18v DC would a MPPT be better? I have a GZ yeti which has built in PWM, however it can take I out from Anderson connections so I could put a MPPT into there
If you're system is 12v, you're fine with pwm, there is not that big of difference but when your system is 18v or higher, it is better to use mppt to maximize the output of your system, getting all that extra juice from the excess voltage and converting them into amps, in turns higher efficiency 😉
Indeed, if I remember it was only 1amp extra with a MPPT.
Yes 👍 🔌 🔋 ⚡ 💡
My PWM controller was £17.99 from Renogy, no brainer for a 100w panel as appose to a £120 MPPT.
Thanks for watching, well this is the big question. I personally would stick with a PWM.
How do you deal with the mppt not starting until Vbat+5 ? My panel is 16.5V in the sun which means it won't trigger the mllt charging until the battery is below 50%
Is the mppt better at battery management also for agm/wet lead acid?
how much power from the battery will pwm and how much mppt will use at night when there is nothing coming from the panels? Thank you.
There should be nothing going the other way. The diode in the charge controlled prevents reversal of current flow at night.
Would be a lot more if the panel was less close to 12v.
Hi Cris what is the voltage of the panel?
Hello, off the top of my head. Think its 18v
MPPT has gotten a lot cheaper no reason to go with PWM. RV industry is still installing PWM controllers I don't know why on a small trailer with one deep cycle lead acid you need every amp you can get if your camping for extended days.
No load charge mppt 13.2v charge battery. On load charge mppt 14.6v charge battery.
Thomas Christopher Miller Ruth Martinez Melissa
PWM is a better choice for 300watts and below 12v solar set up.
Why do you say that
@@mikeb1960he did his research
Amps? Who cares, how many watts?
Amps times volts = watts
@@SolarPowerChannelwithChris Yes. And the watts?
@@Ibian666 don't quote me.. It was an extra amp if I remember right. So an extra 20watts.. Roughly.. Hope that helps.
@@SolarPowerChannelwithChris Compared to what?
@@Ibian666 your mum