SUNYIMA 100A MPPT Solar Charge Controller with LCD Display Dual USB Multiple Load Control Modes,New Mppt Technical Maximum Charging Current (100A)

I bought this figuring that it was not really an MPPT (the claim about it using amperage was a "clue", as was that it only operated 12 and 24v) - but a PWM type controller - but if I got lucky, then great. I was setting up a 12v system for experimentation and eventually migrating it onto my RV, or replacing it or other parts as needed. My set up will push a maximum of just under 30A at the controller, so I felt the 60A unit would be a good safety margin choice... remember that the warmer the temperature on the panels, the lower the voltage, but the higher the amperage. Always factor for those max/mins. So far, it has held up well even with an overheated space I am storing it and the batteries in. It does work well, it does report the voltage, amperage and temperatures fairly accurately, and it does work. So as a nice little PWM controller, it's fine. I held no illusions of it being an MPPT unit, but a lot of people will... so don't be fooled. It's OK, but know what you are buying. For the money, it's a decent little PWM unit, but no, definitely NOT MPPT. EDIT 11/2023 - I just was going back through stuff and thought I'd update - this little unit is still working fine charging my 2x 12v batteries. It's lasted through a cold winter and a very hot summer. Even with a small little 6" fan cooling all components, it's held up and works great. Upped to 5 stars instead of 4 because it's lasted longer than I honestly thought it would, and it just keeps going.

Working very well, and the amp reading is also very nice to have, let me know I wasn't getting as much power as I should be, upon checking I found a bad connection that was causing almost a 75% loss in amperage that my old charge controller showed no indication of. Follow up, as well as it was working it died at 34 days. This is 4 days outside the Amazon return window, considering it took a few days before I could install it it actually worked for less than 1 month. Who knows maybe I just got a bad one I will order a replacement. Stay tuned for info on replacement. Replacement wasn't needed, I disconnected it for about 30 minutes then reconnected it again and it appears to have reset itself, it is currently running just fine and all readings I have verified are again working spot on.

I have four of these controllers (3)60amp (1)100amp over a year I have had others low end quality (cheap price) that burned out in less of a year I have high-end cost one as-well (not china) I do R&D on green energy 1) pro: the price is right (not for large no-manage systems) 2) pro : it has some feature of a MPPT it will adjust V &A to the battery, same watts ( - ) use in the controller . ie: match output voltage high of battery and adjust current to make solar input watt the same , (PWM does not) 3) a 30,40,50,60,100 amp controller is ONLY for the max amp input from the solar panel, these controller only have a max out put of 30 amp (10 awg wire) to battery 4) pro : I like the NEW screen shows amp, volt, C deg less graphic (show number for my testing) with my other test equipment. 5) con: the USB don't work most of the time 6) con: the Kw use screen option is not correct don"t use 7) con: these do get hot if there is 20 amp or more go thru them (I made heat sinks for mine to keep them cool) heat WILL KILL and short the life of the controller 8) con: these are made in china and the safety margin is NOT there, like in other countries, if look at specification take into about 80% usable on max, do NOT think 100% or it will not last long

Cheap caution. Instructions are hard to read

01/10/2021 - I purchased this and a RICH SOLAR 30 Watt 12 Volt Monocrystalline Photovoltaic Solar Panel (https://www.amazon.com/gp/product/B07FN84C9K/) to keep a 12 Volt, 7 Amp-Hour battery charged and to supply power from one of its two USB ports to operate a Wyze V3 camera mounted on a tree outside by a bird feeder; thus making a homebrew solar-powered bird-watching system. My initial system requirements calculations include the following known parameters: The Wyze V3 camera consumes 1.575 Watts of power with night vision IR LED turned off and camera power LED off. MPPT Solar Charge Controller draws 15 mA of current on standby connected to the 12V battery with no external loads. Total power consumed by the camera and controller is 1.755 Watts. Based on these measurements, just over 42 Watt-hours of power would be consumed from the battery every 24 hours. Assuming a new battery is in use, a total of 84 Watt-hours of power would be available so the best-case operation time of the camera with no recharging from the solar panel would be two days. To keep the battery charged would probably require an average of 50 Watt-hours per day from the solar panel due to losses in the battery chemistry when charging and losses in the 50 foot 12 AWG wire (https://www.amazon.com/gp/product/B077Z28343/) from the solar panel and losses in the SUNYIMA 30A MPPT Solar Charge Controller. That would imply the necessity of at least 1.66 hours of sunlight per day on the average. Because my solar panel location can only see the sun for probably 2 hours per day of direct sunlight and maybe another 2 hours per day of partial sunlight due to tree shading I’m hoping the battery will maintain its charge. I did notice the SUNYIMA 30A MPPT Solar Charge Controller voltage display was about two-tenths of a volt higher than what my expensive Fluke meter was measuring at the battery but that’s better than 2% accuracy. I’ll update this review after my system has had some time to operate over varying conditions of solar power output and time in the environment. UPDATE after two days of operation: We've had two days of solid rain and no direct sunlight and the battery voltage has dropped to 11.5V which is still sufficient to operate the Wyze V3 camera since it was installed two days ago. Hopefully the sun will shine again tomorrow and get the battery voltage back up to above 13V. The good thing is even when it is raining and no sunshine there is enough light getting thru the overcast rainy skies to raise the battery voltage about 0.2V during the day and power the camera too. UPDATE on third day of operation: Well, two days of solid rain with no sunshine allowed the battery voltage to drop below the default 10.8V cutoff value programmed into the SUNYIMA 30A MPPT Solar Charge Controller and the camera stopped receiving power. Today the sun came up with no cloud cover and around 11:34 AM the voltage on the battery reached the factory default programmed value of 12.6V and restored power to the USB port for the camera. The panel was shaded in the early morning by trees in the east so that's why it took so long for the voltage to rise from the 10.8V cutoff value to the 12.6V power restore value. I've added a screen capture of an Excel spreadsheet that I'm using to record voltage values displayed on the charge controller and weather conditions. So far the charge controller is doing what it is advertised to do! Update 01/16/2021 - Updated Excel spreadsheet image

Install was fairly easy, the hook up is the same as any controller, but the instructions don't match the actual menu items and how you switch between is a little tricky as the menu time out is short. Second issue is that is not "MPPT" as generally accepted in the industry, so you are probablely not getting what you want. That didn't matter to me, I just wanted a cheap controler with a display. Key word there, display. Display died in less that two months. As for support, returns upto 30 days, prodcut lasted about 45. So no return and I cannot find a support page for the seller or manufacturer. I checked Amazon, the install document, and a Google search. No joy. There are reviews that show this works OK, but not for me. So, I guess the question is "do you feel lucky"?

Made my own generation station for my work and yard battery tools. I have all Ryobi tools 40 volt and 18 volt. I have two 100 watt solar panels attached to this controller. That leads to two marine batteries that go to an an A/C inverter. This controller tells you the amount of sun, voltage levels, current direction and all sorts of other things I do not use. I really like the Smile face emoji that tells you everything is working fine. On sunny days I can charge 2 each 18 volt batteries and 1 40 volt battery at a session. Really have not maxed the system but am happy with what it does.

I purchased a solar panel kit on Amazon which included a cheap controller which would not have likely supported the current draw of my ham radios. This has been a good replacement for that controller. It has more than enough settings, and while using the USB ports to charge my Samsung phone and tablet, both have no trouble charging in fast charge mode. This is a great controller for your ham radio go box.