master battery switch

A/C & D/C Wiring, GPS, Radios, etc.
ddependo
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master battery switch

Postby ddependo » Thu Oct 31, 2019 7:58 am

Helping a friend understand master switch on marinette
single engine two battery setup.
Question : do you leave the switch on all or on house or starter battery?
Does charger work best with switch on "all" or one or two position?
Thanks, Wayne
1973 32 express fly bridge
Chattanooga
"Southern Lady"

Fastjeff
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Re: master battery switch

Postby Fastjeff » Thu Oct 31, 2019 10:35 am

There's room for confusion, that's for sure. Position # 1 on the switch does NOT mean 'one battery' and position # 2 mean "two batteries'. (I wish they had labeled Position # 1 as 'Position A' and Position # 2 as 'Position B'.) "All" (or Both), of course, means 'both' batteries--they got that right at least!

According to Clint's (well-proven) Theory: You can not charge two batteries with one charger--one of the batteries will be 'unhappy' (and so will you when you need it to work!) The opposite is true when you are USING power from the batteries, as when a motor is stubborn getting going.

That said, leaving the battery switch ON (in any setting) tends to draw a battery down since there's often a sneaky parasitic loss in the system that you may not be aware of (such as a memory in something--that's all it takes). The battery in my RV went dead flat after a few months since I left the GPS cord plugged in--that's all it took! And that fool GPS was not even turned on.

Leaving the switch in "All" (or Both) tends to run down one battery, even if no charger is being used. (See above.) So you want to avoid that as well.

Part of my 'Leaving the Boat List' included putting the Perko Switches in the OFF position. Hope this helps.

Jeff
"We live at the bottom of an ocean of air, not at the top." General Marvage Slatington

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Busia
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Re: master battery switch

Postby Busia » Thu Oct 31, 2019 11:22 pm

#1. Every boat is a little different so you have to check and see what works, to learn your boat.
#2. If you want to edit or delete your post, up at the top right of your post are some buttons. Left click on them and you can edit, delete, or quote Jeff on where his money is buried.
BUSIA
located in Ketchikan, Alaska. Gods country
32 foot Marinette express. (no fly bridge)
twin 350 Crusader (Chev 350) engines
1:1 Borg Warner velvet drive transmissions
Closed cooling (antifreeze in the engine)
Proud to be retired IBEW

Fastjeff
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Re: master battery switch

Postby Fastjeff » Fri Nov 01, 2019 6:40 am

..." quote Jeff on where his money is buried."

Those old coffee cans have long ago been dug up and used.

Jeff
"We live at the bottom of an ocean of air, not at the top." General Marvage Slatington

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bcassedy
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Re: master battery switch

Postby bcassedy » Sat Nov 02, 2019 9:15 am

"... Those old coffee cans have long ago been dug up and used."

(sniff, sniff..) End of an era.....

Bill
Bill & Sharon Cassedy
"Sunset Seeker"
'88 32' Sedan Bridge
Located in Aurora, In.
Twin 318cu in Chrysler
1.5:1 Velvet drive trannies
Fresh water only