Charging House Batteries

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mike morasci
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Charging House Batteries

Post by mike morasci »

Due to "other life engagements" I've been away for a few years, but I'm back (formerly mmorasci) now working on my Ultra Pierre the BooBooToo. I swapped out engines to a 4stroke Yamaha 9.9 that is electric start with a charging rectifier/regulator. When I originally designed BooBooToo I kept the house batteries (lights, pumps, fans etc) completely isolated from my starting battery. Now that I have a charging circuit I'd like to have the option of charging the "house" batteries as well as the "starting" Battery. House are two deep cycle marine group 27's while the starting is a much smaller "tractor"battery all are lead acid. House batteries are on an A/B switch with a #10 gage lead running from the A/B switch output, to the stearn in the location of the engine.

Is it as simple as "breaking" the red output wire from the rectifier/regulator where it mounts to the starter solenoid on the engine and setting that output wire as "output" on a second A/B switch with this second switch's "inputs" tying to the starting battery and the #10gage wire going back to the "house" A/B switch?

As a side note, the two house batteries are tied directly to each other (ground terminals) and the hull (steel bottom and transom), while the starting battery is tied to the engine block and hull as well.

Though somewhat complicated, I'd expect to manage the "rear" A/B "charging switch" to maintain the starting battery as primary and would think of topping off the house batteries one at a time as needed by selectively using the house A/B and never use the "both" setting.

Is there an easier way? Any and all comments / suggestions are greatly appreciated.

Mike

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chugalug
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Re: Charging House Batteries

Post by chugalug »

I'm kinda in the same pickle.I'm thinking on using solar panels mounted on roof of "Chug" to charge house batteries.Not sure if my Yamaha 9.9 high thrust has big enough charging system to handle all the batteries.Just not sure how big to go.My roof is 8 ft x 10 ft. :D
Working on regular-sized Bo-Jest


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steveh41
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Re: Charging House Batteries

Post by steveh41 »

If I'm not mistaken the charge output for the Yamaha 9.9 HO alternator is around 6A @ 12V. Fine to maintain the start battery but not adequate for group 27 deep cycle batteries, which would each have a capacity on the order of 90 to 100Ah and require 10-15A to charge properly.

Steve
The longest journey begins with a single step… then repeat as necessary!

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chugalug
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Re: Charging House Batteries

Post by chugalug »

That's what I thought.Don't matter anyway.Canada probably gonna lock out the non-resident tourists again this summer.So won't get to go camping up in the islands and see what I need for power. :cry:
Working on regular-sized Bo-Jest


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mike morasci
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Re: Charging House Batteries

Post by mike morasci »

Thank for the feedback. And here I was all excited to go from an engine with no generator ('61 evenrude 18hp) to one with a charging system that turns out to be too small :(

I did just install a 260watt solar panel on the trailer which frees up a 100watt suitcase type panel I can use on BooBooToo, just thought having a rectifier/regulator would solve my problems.

mike

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chugalug
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Re: Charging House Batteries

Post by chugalug »

Cindy has a Cpap machine that she uses for sleep.We got one with cords that can use 12 volt battery.Unsure of how long that would last.All my interior lighting is LED so not much is used. :D Figure a solar panel with trickle charger might be enough.
Working on regular-sized Bo-Jest


"If it's not crooked,It's not mine

TAB
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Re: Charging House Batteries

Post by TAB »

Many moons ago, mercury use to sell a 9.9 that they called something like "sail power" that had an extra long shaft geared differently and a bigger alternator.

It might have been a 7.5 not a 9.9. I am not sure if they still make them or not

mike morasci
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Re: Charging House Batteries

Post by mike morasci »

All the rectifier/regulator units I've looked at, basically have 4 wires. Two hook up to the stator coils, one is connected to ground and the 4th is the positive that gets tied back to the battery for charging. My electrical skills are weak, but I assume that it is the size of the stator coils and the field generated that determines the amount of current available for "charging". Just installing a higher output rectifier/regulator wouldn't produce any greater charging potential.

mike

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