dumb battery charger question

[scottb7]

2008 210...When I charge the batteries i always set battery switch to 0 so no power goes to the system thinking it could cause a problem. usually i am in the boat wiping it down and i want to listen to the radio without running the battery down. so that is my question: Can i use battery charger with battery switch NOT on 0 and have accessories on? I have no idea. if charger says 10 amp and battery is like 600 amps then I would think no big deal, but I am unsure.

In a car i guess you could battery charge and listen to the radio so why not a boat? probably was a dumb question, huh?

[2002sansac]

No stupid questions here...
From my experience, battery charging should be done with the battery isolated from the boat's electrical system. This means, that the positive ground cable to the battery is not connected to the battery (battery switch in the 0 position in your case), when charging the battery. The reason, as I understand, is that high current from the charger could damage electrical/electronic components in the system. These components could be, alternator, gauges, PP, engine control system-ECM, FI sensors, and others. I am not an EE, so the concern of high current to these components could be incorrect,,,meaning that some of these components could handle the high current and not be damaged.
Do you have any stereo amps, signal processors, etc on the boat?

Dave

[Paxdad]

Do you have an onboard charger or are using a portable charger? If it is an onboard charger and the battery isolater switch in in the off position the batteries will charge but no further current is supplied to the other accessories except the bilge pump provided that your toggle switch is set correctly. If using a manual charger and your battery switch is set to all, 1, or 2 then you can still play the stereo. Keep in mind that when under power your alternator is supply 70 amps back to the entire system while charging the system.

[scottb7]

It is a portable charger. Ok, so we are tied one to one on opinions....That is why i am confused. I agree that if amp is only providing 2 or 10 amps depending on switch then way less then alternator. But what about this whole concept of surface charge? But surface charge does not get over 14 which is what alternator puts out anyway. We need more opinions!!

[Paxdad]

Don't confuse voltage of the alternator with amp output of the alternator. My opinion is that you can use your portable charger while in 2 or 10 amp setting and still listen to your stereo while cleaning boat without harming other engine functions. I would be more concerned with the aspect of running low voltage while listening to the stereo and not charging the batteries. Not an expert so I agree more opinions are a good thing.

[scottb7]

Back to the top...I really do want to know if possible. THanks.

[nyryan2001]

Scott- no issues. Prosport 20 here. do it all the time for over 2 yrs on the same charger. usually keep the batteries at 13.5+ ish while I wipe down and tinker with stuff.

I would not reccomend you attempt to put the switch on 0 or ALL OFF and attempt to run the radio off the battery charger.