Is it safe to have the DC Charging Enhancer (D050S) connected to AC200MAX all the time?

Is it safe to have the DC Charging Enhancer (D050S) fed by a solar panel and connected to my AC200MAX all the time? I have been using my AC200MAX everyday for a few weeks. My AC200MAX gets recharged everyday from two solar panels. I just purchased a DC Charging Enhancer (D050S) to help the recharging of my AC200MAX and noticed clicking noises (every few minutes) from my AC200MAX when the Sun was about to go down. I disconnected the DC Charging Enhancer (D050S) immediately and the clicking noise went away. It sounded like the AC200MAX was trying to switch states continuously every few minutes. I appreciate for any recommendation. Thanks