Battery Charging Control Module Automatic Switch Board HCW-M632 12~24V

First, it's important to understand what this item does and does not do. It's not exactly a "charger", but rather a voltage shutoff switch to prevent over-voltage. It's designed to connect a battery and a source of charging power (like a solar panel) which disconnects the two once the charging voltage reaches a specific user-set value. While you can use this method to at least partially charge the battery, you may not get a full charge. This is because charging voltage is typically higher than battery voltage. As such, the charging voltage will reach your desired voltage and disconnect before your battery reaches the desired voltage. The type of battery will determine how much charge you actually get.My first test was with a solar panel and 12v lead acid battery (full charge typically around 12.8v). This kind of battery has a fairly wide range between full charge voltage (12.8v) and the allowed charging voltage (often 14.5v or higher)...I set the charger to 14.5v and it worked as described. However, the battery voltage was only around 12.6v instead of the full 12.8v. In this case, it was a good 90% charged, so I could get by with it.With other battery types (such as Lithium-Ion) that does not support charging at several volts higher, it was only about 50% charged when reaching the max allowed charging voltage. This is definitely not suited for those.Even with the lead acid batteries, if solar charging is your goal, I would recommend using an MPPT style charger. They'll cost a bit more, but you'll get a more effective charge. You can get by with this, though, If you have plenty of solar energy available and don't necessarily require the battery to be 100% charged.With the 2 buttons not labeled in English, it took me a few minutes to figure out what I was doing. Once I figured out how to set the stop and start voltages, it was simple to adjust from then on.It should also be noted that the LED lights printing the current voltage stay on constantly and cannot be turned off. This is kind of a mixed blessing. It's good because I've put it in a transparent, waterproof junction box and can read the voltage anytime day or night without even opening the junction box. On the downside, these LED lights use some power. For a large battery (such as an automotive or marine battery), the LED usage will be minor compared to the battery capacity. If it's a very small battery, then those LED's could drain a significant portion of your battery. Make sure you pay attention to the power usage specs of this device to make sure this won't be too much battery drain for your particular situation.Overall, given the fair price and the fact that it works properly for what it's designed to do, I will give it 4 stars. But definitely consider the issues/limitations as it may be worth a few dollars extra to get a more efficient charging device.

I have a small sub-pump that keeps water from building up in my shed. This shed is not near enough to the main building to easily run power, so I got a used solar panel and battery, but I found hooking directly to the battery kept overcharging the batterys and getting them quite hot.With this controller I can set what low voltage will to allow charging to start, but more importantly I can set the voltage where it stop charging. No more overcharging the battery in my shed!

Worked great for around 2-3weeks and that was about it. Thinking it died from the heat it seemed to produce. Has no auto shut off feature so controller stays on constantly untill unplugged. This module was not great for a charge controller unless you are only intermittently using it and unplugging every cycle. Might work if your application is not needing a constant power charge controller.