First, users must understand that this controller uses power from the battery to operate. That means that when the solar panel is not able to supply current, the controller will drain power from the battery you are charging. Not a huge problem if you are using automotive sized batteries and a 100w solar panel, but a smaller battery (power sport or smaller) will have significant capacity drained overnight.__Second, the voltage I test at both the battery and solar terminals is unreliable. The voltage at the battery side is usually a half a volt or more low and the solar side is often several volts higher than actual. Yes, my meter has been calibrated.__The USB ports provide limited power except the upper left port which is the only one that doesnt warn that my phone will be

First, users must understand that this contoller uses power from the battery to operate. That means that when the solar panel is not able to supply current, the controller will drain power from the battery you are charging. Not a huge problem if you are using automotive sized batteries and a 100w solar panel, but a smaller battery (power sport or smaller) willl have significant capacity drained overnight. Second, the voltage I test at both the battery and solar terminals is unreliable. The voltage at the battery side is usually a half a volt or more low and the solar side is often several volts higher than actual. Yes, my meter has been calibrated. The USB ports provide limited power except the upper left port which is the only one that doesn't warn that my phone will be "slow charged". This controller works but it has limitations and might not be suitable for every user.

First, users must understand that this controller uses power from the battery to operate. That means that when the solar panel is not able to supply current, the controller will drain power from the battery you are charging. Not a huge problem if you are using automotive sized batteries and a 100w solar panel, but a smaller battery (power sport or smaller) will have significant capacity drained overnight.__Second, the voltage I test at both the battery and solar terminals is unreliable. The voltage at the battery side is usually a half a volt or more low and the solar side is often several volts higher than actual. Yes, my meter has been calibrated.__The USB ports provide limited power except the upper left port which is the only one that doesnt warn that my phone will be