Originally Posted by eljefino
Originally Posted by Kestas
Couldn't a person use an old converter that puts out 12v 500ma?
It would have to be around 13.5 volts.
No!!
an old converter is not smooth DC. a 12V converter will peak up to 17V volts on the DC waveform. A 13.5 will peak higher. If you size it exactly right there will be less of a penalty, but if you don't, you'll overcharge the battery doing more harm than good. I wouldn't leave one of these on for more than a few hours per week if that was the case, and then it's just guessing.
The cheaper smart chargers may still have such a dirty DC waveform BUT they shut off when the averaged voltage reaches 14, protecting the battery. That type then turns back on at 13V.
-m
