For this customer, we have the battery back up system working as the primary sump pump and the back up. NexPump offers an easy to adjust slide switch to choose whether or not your NexPump operates solely as a back up system or as primary & back up. The benefit of this option is the NexPump A.I. controller. This controller performs diagnostics every 12 hours. Diagnostics check pumps, switches, A.C. power, battery, the controller and even the plumbing. It gives you peace of mind and worry-free operation for years to come.Please contact us for a free estimate on your battery back up system or sump pump. We have solutions for every home and business.