Victron Energy SmartSolar MPPT Solar Charge Controller (Bluetooth) - Charge Controllers for Solar Panels - 75V, 10 amp, 12/24-Volt

I have two of these connected to lead-acid deep-cycle batteries. One drives a remote bird-house camera and one powers a pump in a bird bath. They were easy to set up and the instructions are clear. They have enormous programmability. The phone app is great for checking on the battery performance, solar power level, load, etc.There are a couple of features I wish it had. One is more pre-programmed battery types. They offer a few basic battery types and a custom program of gazillions of charging parameters for experts. I'm an electrical engineer and could get out the data sheet for my specific battery and program all the parameters, but what a hassle, and what if I make a mistake? It would be nice to have a few more standard lead-acid battery types in the menu.The unit has a streetlight function for turning on a light at night, but I want a general purpose timer that turns on the load in the day. That would be a small amount of software for Victron to add to the unit and the application. I want our birdbath to run only during the day. I could have used a smaller solar panel and smaller battery if this unit had a timer feature.This unit keeps a history of solar power generated and load power consumed that goes back at least a few weeks. I haven't looked to see how far back it goes, but it's interesting and useful to see how the panels are doing, or if the load is drawing unexpected power. It was also useful to see if my calculations were correct.

I needed to light a tree in less-than-ideal solar conditions using solar power only (charging a 12V battery). I first tried a 12V solar panel with a PWM controller, but it could not keep the battery charged. I found I needed a more sophisticated MPPT controller, so I purchased this Victron Energy SmartSolar MPPT 75V, 10 amp Solar Charge Controller to replace the PWM controller. It worked with the 12V panel OK, but still not good enough to keep the battery voltage in the "safe" voltage drain zone in the poor and varying sun conditions I had (Winter weather, often in low-angle tree shadow).The SmartSolar MPPT controller documentation recommended a 24V solar panel for a 12V battery. I changed to a 24V panel, and it worked great! Using daily measurements from the MPPT controller (via the Bluetooth VictronConnect app), I found that the 24V panel's voltage kept the PV input voltage often at over 20V even on a cloudy day and/or in the shade of trees. The SmartSolar controller converted the extra voltage to the charging power I needed. Keeps my battery charged at above-minimum voltages even on snowy days! Just what I was hoping for! See my chart for my testing results.

Solar is a great thing. Got sun? Free energy! But there is a learning curve to maximize your investment. Victron is one of the shining brands of solar energy, but top-brands don't always mean top-dollar. I was very happy to find this low-cost charge controller to upgrade my DIY power station to MPPT.Quick lesson: MPPT stands for Maximum Power Point Tracking. That's a neat bit of technology that squeezes out as much energy as possible from your solar panels. Must less expensive charge controllers (even if they SAY they're MPPT) are PWM, or Pulse Wave Modulation. Those devices work, but they do not have the extra efficiency to boost solar charging. In fact, MPPT devices like this Victron get you up to 25% more energy over a PWM charger.Back to the topic: This is indeed an MPPT solar charger, rated at 75 volts maximum, 10 amps maximum. You need to know what your solar panel(s) produce to know whether you can use this charger.It lacks a display, though small LED lights report basic charging functions: Float, Absorption, Bulk. And an intermittent flashing blue light lets you know Bluetooth is connected.Speaking of Bluetooth, yes, it's built-in to the device, you don't need a separate dongle. Download the Victron App, use the passkey included with the paperwork, and you have full access to the charger.You can't run many panels with this, probably no more than two, 100 watt panels in series would be best, though you could add three in series and still be within the 75/10 specifications. Check your panels to be sure.It's a great size for a DIY powerstation. A current pricing you could Frankenstein your own 500 watt pure sine-wave for less than $300.It includes a 20 amp standard blade fuse. I'd recommend have a few more on hand. Don't go lower than 15 amp. 20 amp is the device's sweet-spot. It does feature load ports, but no USB.While it's well built and great value, I do have two minor complaints...The wire outlets are really small. I had to double-crimp my ferrules to get them in. And as is the case with several small charge controllers, the openings to tighten the connections are small. I'm surprised these are flat-head screws, too. So if you don't have a small flat-head screwdriver, you'll need one before you can do anything with this.To be honest, Victron has higher voltage/amperage models for just a few dollars more. But if your needs are small and you don't see upgrading later, this will take care of you.

This Victron charge controller is a good choice for small projects such as keeping a vehicle or sump pump battery charged from a 25 Watt (or larger) solar panel. Ability to tailor parameters and monitor performance with a Bluetooth connection is a plus. The unit is dust and moisture resistant when mounted with the terminals facing down. As expected the MPPT buck/boost circuitry assures your battery gets the most possible charge given variable solar exposure. The Victron is more expensive than some, but is brand offers better than average quality and features. It makes sense to invest in a good quality controller to get maximum use and lifespan from your expensive batteries.