Review on 🔋 Sunway Solar Panels Charge Controller 12V Battery Regulator 7A - Enhanced Safety Protection for 12Volt Solar Power Battery Chargers, Solar Trickle Chargers & Maintainers, and Solar Powered System Kits by Collin Donahue

I'm using this to manage a battery, solar panel, and charging subsystem to keep a bunch of small devices charged. Battery 12V 18Ah, solar panel 2 x 20W, load varies from 0 to 1A for up to 4 hours a day. Within this controller, all +ve connections for the battery, panel and load are wired together as is usual with +ve grounding systems. Most modern 12V systems are negative ground: all negative connections go to ground or the chassis. My system was set up as an earth system. The end result is that outside the block all -ve links are connected together and inside all +ve links are connected together. The controller can't handle it and starts smoking after about 20 seconds! My block is on fire. If all sources (battery, panel and load) are isolated or floating with no common connection, this will work fine. This should be a warning to future buyers! You can make it work, but only if the battery panel and the load are not grounded together at the -ve terminal!