In Reply to: Battery Tenders posted by Gary Ostby on December 25, 2017 at 15:07:30:
I think you will get both answers to that question. Yes and no.
On the yes side. The regulator will get confused if you having more than one input to the battery.
On the no side. The amount the tender is putting in will be of no consequence.
On my boat, I turn off the solar panels before I start the engine. Using the yes principal.
Around here, I often start a bike or the cage, using the no principal.
Sometimes folks that sell battery tenders and solar panels, are not aware of, or do not know the correct answer. I read the books written by the smart guys, and they sometimes differ. Like using a fuse between the alternator and the battery. No if the wyre is direct, yes if you have a clever distributing unit for more than one battery.
I have 4 battery tenders, and one solar panel taking care of batteries at the moment. That does not count the boat. Stupid cage has a .78 amp drain when the key is off.