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[uhtrinity]

I want to add some more information related to the chargers output voltage. This will apply to the 'dumb' chargers like the Meanwell based units.

So far I have set up two cars with dual battery packs and dual chargers. My car charges fine and has a reasonably safe charging profile. However my friends Insight has had some charging issues, mainly battery over heating.

My charger is set to 170.5 volts (post diode at the battery terminal) and has a profile of bringing the battery from 140 volts to 169.5 volts in roughly 8 - 10 hours. This is with a 130 - 140 watt draw at the outlet. When out of sunlight it will then drop to 30 - 50 watts and maintain this charge level until the battery pack heats up and the pack voltage level starts to drop. This allows a ~14 - 18 hour charge on a normal summer evening and morning. Charging in full sunlight is not recommended.

My friends charger was set to 171 volts. This minor difference made it so his charger never dropped charge level and resulted in battery temps of up to 60C or 140F and it would happen often unless unplugged within 8 - 10 hours. Even sooner if the batteries hadn't been drained enough. We have since dropped his charger voltage to 170 volts and he now sees the dip to 30 - 50 watts along with normal ambient battery temps.

Since the Meanwell Chargers will supply full current (350ma per unit) to within 0.5 volts of the battery pack I recommend caution if leaving the charger unattended. The safest course of action is to lower the voltage (post isolating diode) to 170 - 170.5 volts.


edit: I want to add that since I started using this method my batteries have been at 168 - 170 volts every morning and get a 'key on for 2 minute positive recal" 100% of the time. Balancing should still be taking place on those morning when the charger is 'accidentally' left on until midday.