What is a combined MPPT/PWM Solar Charge Controller 100A?

[sun walker]

Hi, So I'm replacing a small old off grid with a new 7.5kw off grid, & being poor seek best value for my mppt, after long searches I find this ~$25 US each, sold on many online retail, Its sold as a mppt but I'm not sure what it is, What is a combined mppt/pwm? I know what they are, but not what this is, Amp's too high for a pwm?
Can't find the company that makes it "https://kinsunsolar.en.made-in-china.com/" list all their products factories, except this.
I'm trying to keep post small but can provide more info.

Any information thoughts welcomed.

Sorry about the "bold" its all copied & won't unbold.

"MPPT/PWM Solar Charge Controller 100A/80A/60A 12V/24V/36V/48V Auto Solar PV Battery Charger "​

"aliexpress.com

MPPT DC 12V/24V/36V/48V AUTO 80A 100A Solar Charge Controller PV Regulators Solar Battery Charger for Lead acid battery"

NOT the Real MPPT.

"https://www.solarhm.com/portfolio/items/12v-24v-36v-48v-96v-60a-80a-100a-pwm-solar-charge-controller

This SYC series PWM solar charge controller is a LCD solar controller which is used in the off grid solar system.

12/24/36/48V 100A MPPT Battery Charger Off-Grid Solar System Charge Controller 736542902648 | eBay

Find many great new & used options and get the best deals for 12/24/36/48V 100A MPPT Battery Charger Off-Grid Solar System Charge Controller at the best online prices at eBay! Free shipping for many products!

www.ebay.com

"Specifications:

Name: Solar MPPT Controller​

Material: plastic and aluminum​

Current: 80A, 100A (optional)​

Input voltage: DC12V/24V, DC36V, DC48V​

Output voltage: DC12V/24V, DC36V, DC48V, DC5V/1.5A*2USB​

Working temperature: -25℃ to 55℃​

Item size: 198 * 180mm / 7.80 * 7.09in​

Package size: 195 * 184 * 66mm / 7.68 * 7.24 * 2.60in"​

 

[yodamota]

in my opinion this is not your best value. What exactly are you looking for? What is your system going to operate at?

is it a 7.5kw battery? or 7.5KW of solar?

 

[sun walker]

in my opinion this is not your best value. What exactly are you looking for? What is your system going to operate at?

is it a 7.5kw battery? or 7.5KW of solar?

Hi, thanks for your reply.
17 x TW415w pv (7.5kw).
Lithium Batts still researching, but high storage 48v probably (12v series).
My house is wired for 12v, I use an array of inverters (small old system).
My plan is to run a 48v line to a small A/C unit, kitchen appliances, and washing machine, maybe small freezer.
Plus a high batt voltage sensor & relay to dump power to a 12v hot water element/tank.
Next mppt option would be POWMR? 80A non fan heat sink from factory ~$70 US.

 

[45North]

You know the saying "if it's too good to be true"
True mppt's cost a lot more than PWM controllers, so beware of false advertising and mislabeling.

 

[yodamota]

Hi, thanks for your reply.
17 x TW415w pv (7.5kw).
Lithium Batts still researching, but high storage 48v probably (12v series).
My house is wired for 12v, I use an array of inverters (small old system).
My plan is to run a 48v line to a small A/C unit, kitchen appliances, and washing machine, maybe small freezer.
Plus a high batt voltage sensor & relay to dump power to a 12v hot water element/tank.
Next mppt option would be POWMR? 80A non fan heat sink from factory ~$70 US.

being that I live in a remote location. The last thing I want is for a component to fail because it was cheaply made. Being offgrid for 8 years now, I have luckily not had any issues because of this. I started with good components and it has paid for itself it full.

Lets start with the outback we have. Today it costs me around 1000$ Canadian to buy. So far it has lasted me 8 years of use. 1000$ / 8 years is 125dollars per year. This number gets smaller every year.

I think If i was trying to spend the absolute lowest amount of money I would look for an EPever https://www.santansolar.com/product/epever-8420an-80a-mppt-solar-charge-controller/
I am sure there are other options.

 

[sun walker]

being that I live in a remote location. The last thing I want is for a component to fail because it was cheaply made. Being offgrid for 8 years now, I have luckily not had any issues because of this. I started with good components and it has paid for itself it full.

Lets start with the outback we have. Today it costs me around 1000$ Canadian to buy. So far it has lasted me 8 years of use. 1000$ / 8 years is 125dollars per year. This number gets smaller every year.

I think If i was trying to spend the absolute lowest amount of money I would look for an EPever https://www.santansolar.com/product/epever-8420an-80a-mppt-solar-charge-controller/
I am sure there are other options.

That`s a very expensive site, I have considered this mppt, its a similar cost as powmr above....all made in China. If I had the cash I would probably chose mppt Outback for its power dumping ability.

But I'm still very curious as to what a combined MPPT/PWM is?

For the price I could have 1 or more spares, my concern would be frying my batteries, but I could install an addition overcharge relay between them & it. I need 3 so I guess if I buy 1 and test it , may be only option.

​

 

[pollenface]

But I'm still very curious as to what a combined MPPT/PWM is?

Misleading advertising.

 

[Rednecktek]

But I'm still very curious as to what a combined MPPT/PWM is?

A scam to get money out of suckers. It means "PWM but we typed MPPT on it because we can get away with it and people who don't know better will give us money".

The 2 biggest giveaways that it's PWM and they just wrote MPPT on the sticker is 1: the price is less than about $75 and 2: very VERY few true MPPT controllers have USB on them.

 

[Whats_per_question]

To veer off topic for a moment ...
To some extent, there is a valid justification to using the acronym "PWM" in the specs of an MPPT controller, but no justification or weasel-words that will make it ok to add "MPPT" to a PWM controller specs.

With a true MPPT controller, there is a PWM element - the controller uses pulse width modulation to change the duty cycle of some parts of the circuitry to achieve the desired effects. This Instructables project is a great walk through of how an MPPT works and even if you never ever want to build an MPPT controller, you should read (or at least skim) this tutorial and you will gain a wealth of understanding of how a true MPPT controller works, and you don't even need to pick up a soldering iron.

Having said all that, my opinion matches @Rednecktek - the auction/sale the OP refers to is just a scam to sell cheap PWM controllers to unsuspecting customers.
Another scam going on in NZ at the moment is "modified sine wave" inverters flooding the cheap end of the market, some being listed as "pure sine wave"

 

[TommySr]

This Instructables project is a great walk through of how an MPPT works

Whats_per_question, Sweet link!