Authentic MPPT Solar Charge Controller 15A 12V/ 24V Waterproof (MPPT1575)

With no reviews on this charge controller, I was hesitant to purchase it. So many other low-cost charge controllers aren't what they claim to be. When the box arrived, my optimism grew as I felt that the controller had a solid, heavy feel that I've only seen on true MPPT charge controllers. The aluminum casing is thick, durable, and well-sealed. I would feel confident using it in wet environments, and I think that it would perform to the IP67 rating that it claims to have.This charge controller is as simple as they get. There are no buttons whatsoever. It has two LED lights to indicate status, one green and one red. There is a one-page (front and back) user manual included in the box. The english in the manual isn't perfect, but it is very understandable. The charge controller appears to have an infrared emitter and receiver, but there is no information that I can find on how to use it. Therefore, the default configuration is the only configuration. It has what appears to be a temperature probe, and the user manual indicates that it compensates the boost, equalization, and float voltages for temperature. All the wires you see on the charge controller are permanently sealed to the charge controller. They are all 14-gauge stranded wires; which is sufficient for the 15-amp rating of the charge controller.To test the charge controller, I used a 100-watt HQST flexible solar panel with voltage/amp/watt meters to monitor power from the solar panel, and to the battery. When I first got everything hooked up, I was afraid that I had a bad charge controller. The green LED light indicated that there was power from the battery, but it didn't start flashing for what seemed to be about 60 seconds. After I had almost given up hope, the Green LED started flashing rapidly to indicate that the charge controller had entered MPPT charge mode. With the cool but very clear and bright daylight conditions, these are the readings that I observed:Metrics for the power from the solar panel to the charge controller (on average): 15.2 volts, 5.5 amps, 84 wattsMetrics for the charging current from controller to the discharged battery (on average): 13.2 volts at 6.21 amps, 82 watts.The conversion to lower voltage and increased amperage in charging indicates MPPT functionality, and when you factor in that the short-circuit current rating for the panel is less (6.10 amps) it removes all doubt. This is definitely an MPPT charge controller!I am very impressed by the efficiency of this charge controller. The wattage consumed by the charge controller in MPPT charging mode is very minimal at about 2 watts (give or take accuracy of my meters). After an hour of charging at these rates, the charge controller was still room temperature.If you need to change the voltages for your specific battery then this is not the charge controller for you. However, the factory default and unchangeable voltages seem ideal to me for most 12-volt batteries. At 75 degrees Fahrenheit, this controller charges MPPT up to 14.5 Volts (the boost voltage). The equalization voltage is 14.8 volts (I don't know how often or how long the equalization cycle is), and the float voltage is 13.7 volts. If the temperature compensation is effective then these numbers should drop for higher temperatures.This charge controller lacks any kind of screen, and the information that you can collect from the LEDs is limited. If you are a numbers guy like me then this is easy to remedy with a volt/amp/watt meter that can be purchased on Amazon for about $15.If you need a very simple but effective charge controller, I believe this is an excellent option. I cannot speak to the reliability/durability of the unit, but everything that I have seen and tested thus far seems true to specifications. For around $50 you simply cannot beat it. The waterproof feature is also a big plus. I hope this review is helpful to you.

Lots to talk about. I have four off-grid systems ranging from 100w to 4,900w arrays. Do A LOT of testing of solar products. Here is real truth about this solar charger:MPPT - yep, it is...it actually cycles through it's "hunt" cycle every 60 seconds. Even though a solar panel will state that it's VMP (for example) is 18.5 volts, it may not RUN at that voltage for MPPT. I have seen this charger HUNT all around for the maximum current...and then find it at lower voltages. VMP depends on MANY factors to fall in line....like temperature, shading, clean panels, etc-etc. So, a "typical" 100w solar panel may have a VMP of 18.5 or so...this solar charger may not OPERATE it at a LOWER voltage.CHARGING - This unit looks like a good match for AGM (SLA) type batteries. FLA will be fine. I have seen 14.5 volts when it does it's self-appointed EQ charge. FLOATS at about 13.3 voltsAUTOMATIC - No bells or whistles...or adjustments. Kinda takes the head scratching away from DIY solar...but, the parameters seem good and close to what the literature statesSMALL - Wires are short...so, be careful splicing and connecting. Connect the battery wires FIRST. Read the directionsTEMP SENSOR - Kinda a cool addition...dunno if it is actually working. But, time will tellOVERALL - Entry level 15-amp 12/24v MPPT solar charger with NO ADJUSTMENTS. I have several videos on my Chris DIYer YouTube page showing this unit in action. But, it seems to do very well...glad I got one (may get another one).

Initial Review [15-Sep-17]Finding this particular unit in-stock is hit-or-miss. But after missing out one batch it became available a week or so later. Was delivered in just a few days even without Prime. The unit itself was surprisingly (and pleasingly) small. Others have dissected the package and determined that yes, it does have a decent-sized transformer as necessary in a true MPPT controller. I'm not going to compromise the environmental sealing to inspect myself. The legend is silk-screened to the case but the manufacturer name is a transparent label, leading me to suspect GreeSonic is not true manufacturer. A search of other GreeSonic products shows the brand focuses on solar power, so they should have adequate knowledge of the industry and standards (I hope!).The connections for the PV, battery and load are 14 AWG, which is smaller than I'd like. Even though the controller is only rated for 15A, 10 AWG wiring should be used to allow length for organized cable routing without excessive voltage drop. However, these leads are short (around 6") and probably won't result in significant voltage drop. I'm also not going to connect my load directly to the controller; I'm going to use a separate DROK multimeter to supervise battery levels and control my load via a 200A solenoid. I just need to figure out what connectors to use to accommodate 14 AWG the controller side and 10 AWG on the battery and PV side.The status LED's are on the bottom of the controller, where the cabling exits. That will make visibility a problem in my setup inside the camper's bench compartment unless I mount the controller upside down in the cabinet. Hopefully, this won't cause any cooling issues.I'm still waiting for components to install this, particularly the PV panel. I will update this review after I get everything running.