Battery switch confusion

Jul 26, 2021
3
Hunter 356 Chesapeake Bay
Just purchased an ‘02 356. During survey, it was noted that when battery switch is positioned in “Off” position, DC panel still gets power. Only way to kill power is to flip breaker off on switch panel. I have tried multiple positions to determine which are house and starter batteries, but all positions give me the same results; everything is powered unless breaker is thrown…any guidance would be greatly appreciated!
 
Sep 25, 2008
7,077
Alden 50 Sarasota, Florida
Find the previous owner and charge him with negligence. The boat didn't come out of the factory wired like that.

All DC power should flow through the battery switch (with exception of bilge pumps).
 
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Likes: ggrizzard
Jan 18, 2016
782
Catalina 387 Dana Point
Break out a multimeter and start tracing from the batteries. Something is wrong. Something may be very wrong - i.e. something like a 12g bilge pump wire is powering the entire panel (If unfused, that could be a very bad thing).

Trace em and make a wiring diagram.

Could also be a switch that was broken in one of the ON positions. All of this is easy to find out with a simple trace of the wiring.
 
Sep 11, 2011
390
Hunter 41AC Bayfield WI, Lake Superior
Johnny: Our 41AC 2004 came from the factory the same way. Only the main DC breaker shuts everything down, except the bilge pump, and stereo memory. The start batery is totally isolated from house loads, unless the yanmar is running and then a solenoid activated switch combines the batteries for charging purposes. There are many discussions on the site about this.

At about the time these boats were being built many inverter/chargers were being installed and I would guess that is when the electrics started to get mixed up. Many of the electric schematics are available for many of the Hunter boats. You may be able to get a copy and see what was changed........or you can go sailing and ignore it.
 
May 24, 2004
7,129
CC 30 South Florida
House batteries are usually deep cycle batteries rated in Amp/Hours, either 6V connected in pairs or stand alone 12V batteries but all DEEP CYCLE. Starter Battery is usually a single 12V battery rated in Cranking Amps rather than Ampere/Hours. Now many sailors will dedicate a deep cycle battery for starting duties but never a Starter Battery for house duties. Hope this may help you identify which are the house batteries. Now there is no easy way to predict what a previous owner may have done by mistake or for convenience so you may have to trace the wires coming off the batteries to the battery switch and identify any other wires which may bypass the switch. When you say the panel is powered, with the switch Off conduct a simple test, turn On the cabin lights breaker and see if the lights come On. Also try cranking the engine and see if it cranks. If both of the tests do not turn anything On I would not discard the possibility that your panel may have some low voltage courtesy light hard wired. I personally always will turn both the panel breaker Off and the battery switch Off when leaving the boat. Should your panel breakers be powering the appliances then there is a problem that requires prompt attention as the panel breaker will not turn Off any power in the wires leading to it.
 
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Jan 5, 2017
143
Hunter 356 SF Bay / Delta
My 356 had some odd wiring done at the battery switch as well from the PO. Switching to off would show 6v at the DC panel!

MH has the wiring diagrams available from their website that tell you where the orange/green and orange/red wires go. On my boat, the #1, #2 and Engine Positive were all labeled in sharpee -- I assume that was done at the factory.

I dug into some old photos and I believe this is the picture we took after correcting the wires. We've since changed the configuration as we've gone to a lithium house bank.
 

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