Battery question

[TnT]

Once upon a time, I was told that when you charge your cranking battery, the negative post needed to be disconnected if you were charging at more than 2 amps to keep from burning out the power pack. I have 2 questions about this:
#1- Is this true?
#2- If it is, doesn't that defeat the purpose of an on board charger that charges at 5 amps per bank?

[Charger]

I have never heard that. I never disconnect mine and have had no problems. I would assume there would be a diode protecting that circuit.

[rockmike]

Never heard that, and I've never done it, and I've never burned out a power pack. I use a 10 amp on-board charger all the time.

[Barnacle Bill]

I suspect that come about by someone that had the habbit of connecting the charger up backwards. I wouldn't hurt the power pack but it would sure blow the rectifier/regulator in a heart beat. If done correctly it won't hurt a thing.