Why do I need to disconnect the battery when using my new trickle charger?

The instructions that came with the 6/12v 740/4355 automatic battery charger I bought from Argos yesterday say “disconnect the battery from the vehicle before charging to avoid possible damage to the alternator”. That could lose the radio code without a slave battery. Is this normal?

Asked on 5 October 2013 by MD, Ringwood

Answered by Honest John
Yes. You bought the wrong type of charger. You should have bought a 'Battery Conditioning Trickle Charger'. Nothing needs to be disconnected when using one of them.
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