sailboatmike wrote:You need one of those fancy intelligent isolation switches that charges the start battery first and then switches over to the secondary battery, was looking at one myself just the other day but seriously doubt I will get that mod done in the short term, many other pressing things need to be done to get the boat better to sail before I worry about that stuff.
Battery up-grade
- dlandersson
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Re: Battery up-grade
"fancy isolation switch" = Perko switch.
- Sumner
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Re: Battery up-grade
sailboatmike wrote:You need one of those fancy intelligent isolation switches that charges the start battery first and then switches over to the secondary battery....

Installed one on the Endeavour this past spring...


... more on it here ....
http://1fatgmc.com/boat/end-1/endeavour ... age-5.html
Sumner
============================
1300 miles to the Bahamas and back -- 2015
The MacGregor 26-S
The Endeavour 37
Trips to Utah, Wyoming, Idaho, Canada, Florida
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- sailboatmike
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Re: Battery up-grade
Can anyone tell me waht rating of "Fancy Switch thingy" I need??
I see they are rated in AMPs, but is that amps being drawn or the amps of the battery storage.
I have 2 x 720cca Start / 105ah duel purpose marine batteries
I see they are rated in AMPs, but is that amps being drawn or the amps of the battery storage.
I have 2 x 720cca Start / 105ah duel purpose marine batteries
- kadet
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Re: Battery up-grade
To combine and use for starting?sailboatmike wrote:Can anyone tell me waht rating of "Fancy Switch thingy" I need??
I see they are rated in AMPs, but is that amps being drawn or the amps of the battery storage.
I have 2 x 720cca Start / 105ah duel purpose marine batteries
Then you need the draw amps they normally have continuous and momentary amp ratings. The momentary will need to be at the rating of your engine's starter not the battery. Mid size outboards draw about 300 cca, check your manual, so then you would need a 100/300amp dual battery switch.
If you are talking about charging then the rating would need to be more than the charger e.g 25+ for a 20amp charger.
It is best not to run electrics close to their maximum amperage for long periods this is why I say 25+ for a 20amp charger.
- Phil M
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Re: Battery up-grade
Highlander - I'm not sure about putting electrical connections and Perko switch at the front facing bottom of the companionway ladder. That area is subject to kicking and bumping with feet, and more specifically my feet.
If something can go wrong, it will. 
- Highlander
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Re: Battery up-grade
Yes & U,ll notice in this pic my little bottom black step extension to protect themPhil M wrote:Highlander - I'm not sure about putting electrical connections and Perko switch at the front facing bottom of the companionway ladder. That area is subject to kicking and bumping with feet, and more specifically my feet.If something can go wrong, it will.
http://i844.photobucket.com/albums/ab1/ ... dgmgsl.jpg
J
- Phil M
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Re: Battery up-grade
Yeah, good idea.Highlander wrote:Yes & U,ll notice in this pic my little bottom black step extension to protect themPhil M wrote:Highlander - I'm not sure about putting electrical connections and Perko switch at the front facing bottom of the companionway ladder. That area is subject to kicking and bumping with feet, and more specifically my feet.If something can go wrong, it will.
http://i844.photobucket.com/albums/ab1/ ... dgmgsl.jpg
J
My Perko switch is mounted on the adjacent right side, and I have still managed to clunk into it with my feet.
- dlandersson
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- paula_ke
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Re: Battery up-grade
I had an interesting experience with my automatic battery charging switch. Some how I managed to deep discharge my house battery while sailing. Starting the motor was not an issue as the automatic switch had them separated. It seems I had not full charged the house battery before going out and ran it down with the fridge, vhf, stereo and Garmin. Sooo, I had no Garmin for nav or depth sounding.
After anchoring I poked around and found that the starter battery was fully charged and the motor running showing solid voltage for charging. But the automatic switch would not connect the house battery to get charged. My house was well below where I like to see it. Around 7 volts.
I have a non permanent solar setup with two 100 watt flexible panels and a good charge controller that is set up to charge house. I connected that up and the house battery quickly recovered to 11 volts.
I started up the motor and sure enough, the automatic switch connected the starter battery / motor to the house and accelerated the charge recover.
So, it seems that the automatic switch detects if a battery is over discharged and will not connect the two banks.
Good to know!
Captain Paula of the good ship AirWave

After anchoring I poked around and found that the starter battery was fully charged and the motor running showing solid voltage for charging. But the automatic switch would not connect the house battery to get charged. My house was well below where I like to see it. Around 7 volts.
I have a non permanent solar setup with two 100 watt flexible panels and a good charge controller that is set up to charge house. I connected that up and the house battery quickly recovered to 11 volts.
I started up the motor and sure enough, the automatic switch connected the starter battery / motor to the house and accelerated the charge recover.
So, it seems that the automatic switch detects if a battery is over discharged and will not connect the two banks.
Good to know!
Captain Paula of the good ship AirWave
- mac n cheese
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Re: Battery up-grade
Hello Paula. I'm curious...is your automatic charging relay (ACR) made by Blue Sea? Did you notice the LED flashing during the house battery severe discharge?paula_ke wrote:I had an interesting experience with my automatic battery charging switch. Some how I managed to deep discharge my house battery while sailing. Starting the motor was not an issue as the automatic switch had them separated. It seems I had not full charged the house battery before going out and ran it down with the fridge, vhf, stereo and Garmin. Sooo, I had no Garmin for nav or depth sounding.
After anchoring I poked around and found that the starter battery was fully charged and the motor running showing solid voltage for charging. But the automatic switch would not connect the house battery to get charged. My house was well below where I like to see it. Around 7 volts.
I have a non permanent solar setup with two 100 watt flexible panels and a good charge controller that is set up to charge house. I connected that up and the house battery quickly recovered to 11 volts.
I started up the motor and sure enough, the automatic switch connected the starter battery / motor to the house and accelerated the charge recover.
So, it seems that the automatic switch detects if a battery is over discharged and will not connect the two banks.
Good to know!
Captain Paula of the good ship AirWave
It should fast flash below 9.5 vdc.
I have the Yadina 100 ACR combiner which only has 2 LED's ( combined and overload). These combiners complete a dual battery installation for sure. A great mod.

- paula_ke
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Re: Battery up-grade
Yup, Blue Sea. Don't recall looking at the ACR just took my multimeter and measured the house. It was clearly to low. I used the solar charger to recover above 11 volts and all worked like it should. so the ACR behaved as it was suppose to. Keep things isolated if the one battery is to low.
Captain Paula of the good ship AirWave
Captain Paula of the good ship AirWave
- Highlander
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Re: Battery up-grade
Also here,s the buss fuses I added to the battery poss, on all three battery banks


Aft house bank 2 golf cart 6vlt batt,s

Start batt.
http://i64.tinypic.com/2vkkql4.jpg
second house battery bank is up under the V Berth
J


Aft house bank 2 golf cart 6vlt batt,s

Start batt.
http://i64.tinypic.com/2vkkql4.jpg
second house battery bank is up under the V Berth
J

