More on a 'Battery Tender'

Yup, paranoid. The charger is built around a transformer that isolates the 120 VAC power input from the DC output. Reversing the plug does not affect the DC output in anyway.

Having a third prong would permit the (metal?) case of the charger to be grounded. This means that an internal short in the charger would not give you a shock. But it is just as safe to make the case out of an insulator such as plastic and physically arrange the wiring so it cannot chafe or break.

Just now I connected the tender up and get proper indicator lights and voltage polarities no matter which way I connect the plug.

So I would think that you are indeed very right.

Thanks for reply

One day I will find my short though. Now up to 7V! Must be the starter itself.

Cya

If the battery is good, it should be unnecessary to use a battery tender during the mowing season. If you use the mower once a week for a half hour or so, that should keep it charged. The tender is needed in the winter, when the battery isn't being charged by the mower. And I sure wouldn't use it to allow leaving the battery connected. Until you find the short, the battery should be disconnected after each use.

That assumes the charger circuit in the mower is working right. My original was not and many people with Craftsman complain about the same thing.

Hope this is not a joke. The AC reverses 60 times every second so it will not mater which way you plug it in as far as the output to the battery.

Nope - not a joke. Just a question out of ignorance.

Thanks for reply.