I bought four of these chargers to make a charger bank for a 48V scooter. For various reasons, I discarded the charger bank idea in favor of a serial / parallel plug setup. I then rewired a plug for a single charger to put 12V into all four batteries in parallel. This system has been working for two successive scoots over the last three years.
Over time, they got noisier and noisier, as the plain bearing fans gave out. One unit was forgotten in the rain and self-destructed in its logic circuits somewhere. I finally lost patience and replaced the cooling fans in the remaining three units. They are back to the "cool, calm, and collected" units I remember from when I first bought them.
Still going strong. The digital readout of amps and volts is very useful.