Q: Regarding last October’s RV Clinic “Take (Float) Charge”, if keeping your RV plugged in can lead to excessive battery water use, how do those who go south for the winter and stay plugged in at an RV park for months at a time manage to not overcharge their batteries? I’ve found no way to have electrical power to my coach without going through my coach batteries. When I disconnect my coach batteries using the battery disconnect switch by my door, I end up with no electrical power to the coach. Could my disconnect switch be defective?
Ronald Gjestson, Bozeman, Mont.
A: The disconnect switch is designed to electrically disconnect the battery from the coach during storage, to prevent it from becoming discharged by parasitic draws, so it is doing what it is supposed to do. It is not designed to disconnect the battery from the charging circuit. Having a battery in the circuit helps “smooth out” the AC ripples from the converter’s output. This helps ensure that circuit boards and other sensitive devices get the smooth DC power they need to operate reliably. The problem is that not all converters are designed with multi-stage charging circuits and as a result they tend to overcharge the batteries and cause them to use excessive water. The solution, if you have a single-stage converter and are having problems with batteries, is to replace it with a smart converter such as a Xantrex TRUEcharge2.
– Ken Freund