I have 3 generators that while producing (even though they aren't producing or if they are it is negligible) show 19.5 volts, 21.4 volts 21.4 volts and 3.89 amps, 3.94 amps and 3.94 amps. When not producing they have 26.5 volts, 27.3 volts and 27.8 volts. I know all these numbers are too low. I replaced one of the current limiters just to see if it would make a difference and it did not. The units are 7 years old. I have 2 sets of new cells to experiment with but nothing changes when I swap out cells. The salt content is 3200. Does anyone have any suggestions?