I bought a Wanderer 30A PWM solar controller and it failed after about 2 months of use. First the charge voltage was too high, and then the regulator got stuck on fast charge. I contacted Renogy support twice. First I was told that there was nothing to do with floating voltage and after the controller got stuck on over voltage, when I spoke to the support they told me that my battery was bad, they wanted to know when I bought it and insisted that I reconnect the bad voltage. controller and take a picture of my DVM showing the battery voltage readings and the controller output that would cause the battery to overcharge. At the moment I am using a HQST 10A charge controller which works as it is supposed to. I strongly recommend not using Renogy controllers as they DO NOT SUPPORT their product!