A quick test of all my battery regulators with the original chargers showed that they all work properly. They start shunting a bit of current at 13.0V and by 13.7V they are just barely glowing. At 15.0V they are shining nice and bright.
I also installed my new Kelly charger. First off, I will say this charger performs just as it was designed to. Unfortunately, this is a big problem. Why? Because when I hastily ordered this charger, my pack was mostly flooded lead acid batteries. Now my pack is all AGM batteries, which requires a lower charging voltage.
This charger holds 88.2V (14.6V/battery) during the absorption charging stage which is proving to be too high. According to the battery specs, this is an okay voltage at the current temperature (10C), but it seems that with series charging, this voltage is making things go...well....wonky.
The bulk charge stage is fine. All voltages are even and slowly climb to 14.0V/battery and my regulators all start glowing nicely. But as soon as they go over 14.1V, a couple of batteries quickly shoot up to 15.2-15.5V (making my regulators glow very bright!) and after a while a couple of batteries go down to 13.8V. 15.5V is very bad for these particular AGMs because it can cause electrolyte bubbling at too high of a rate which may cause them to vent. Once AGMs vent, they quickly degrade because there is no way to fill them back up with electrolyte.
So...I have ordered another 7210 Kelly charger - this time with a constant voltage of 84.0V (14.0V/battery) and a float voltage of 81.0V (13.5V/battery). My current one shouldn't be difficult to sell because it has the correct charging profile to be able to charge lithiums.
Anyone in the market for a 72V/10A (88.2V max) charger?
