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correct wiring for dual engines-dual batteries each 1 house battery switch each -3 bank charger ?

Understood.
Will it work? Yes.... it will work!

However, I'll not recommend to anyone that they select ALL/BOTH for charging.
Reason; I want the alternator to sense each bank independently.
Plus, a cranking bank will generally recover rather quickly after start-up, given that the engine is quick firing to begin with.

If alternator charging of both banks is a concern, I think that an ACR will better serve the purpose. IMO that is.


I think that this thread is turning into one of those "Gone with the Wind" threads! :D :D :D


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....However, I'll not recommend to anyone that they select ALL/BOTH for charging.
Reason; I want the alternator to sense each bank independently.
Plus, a cranking bank will generally recover rather quickly after start-up, given that the engine is quick firing to begin with.

If alternator charging of both banks is a concern, I think that an ACR will better serve the purpose. IMO that is.....

Rick, this is precisely the reason I suggested earlier for not hooking up a crank bank to a house bank with an ACR. An ACR will NOT make this any better. It will not direct currect to a bank that needs it the most. It simply closes when it sees a charge voltage. It will do exactly what you are saying should not be done with an ALL/BOTH switch for charging. I don't want to be a pest or go on and on with this thread but I'm either missing something or simply not reading you right but it's clear in the diagrams that the cranks and deep cycles can be charged from the same source under normal conditions which you say should not be done. Right, no? This is why I've been saying to use an ACR between the two starting batteries off one alternator, and the house gets charged by the other alternator (no ACR). For the abitly to charge house and cranks should an alternator fail, simply hook up a latching solenoid (not 1,2,ALL switch)controled from the helm and incorporate a pilot light so you know at a glance from the helm that the banks are paralleled and can then switch off from the helm when back at the dock; simple, easy, no guessing/switch management needed....IMO of course:)
 
Coincidently, guess what I just got called upon to investigate today? After having three cranking batteries fail; one each season for the last three seasons, and all others on board ok yet same brand and age, a battery distributor asked me to check the wiring on this vessel as a possible cause. This is what I found: 3 years ago, a bow thruster had been installed. As part of the thruster installation, a 31 series crank battery was installed, and for charging purposes, the installer had inserted an ACR between it and the HOUSE (3 batteries) bank. This boat saw a lot of use on the hook, as such, the house bank was used constantly and bringing it low enough to require such a charge that it would put the thruster crank battery into an over-charge condition repeatedly. The boat owner always wondered why that battery always failed and why its fluid was always low even though he had a smart charger on board. Unfortunately for him, upon reporting this to the distributor, the battery replacement will not be covered by the manufacturer this time! This is a perfect example of the conditions I mentioned before that I've been coming across over the last couple of years. Had they hooked up the ACR to one of the engine batteries, this wouldn't have been a problem. Perfect timing for this thread!
 
Woodie, which ACR? Apparently Blue Sea had a recall on some of their smaller ACR's a while back.


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Woodie, I certainly appreciate your knowledge and thoughts on this.
I just took another look at the schematic that I made.

First, are we in agreement that the ACR activation voltage is 13.5 volts?
If so, and if you were to look at the ACR for the two cranking batteries, you'll see that once either of these two batteries reached charge voltage, the ACR should let go.

In theory, the Stbd MBSS Common terminal would now direct the alternator charge towards the Stbd side HLBB ACR.
The Port MBSS Common would then direct the alternator charge to the Port side ACR.

Many people use the Blue Sea ACR in order to take advantage of a charge from both engine alternators for their HLBB's.
Keep in mind that any of these ACR's could be the 7622 with the remote switching and lock-out capability from the helm area.

Agree...... an MBSS set to ALL/BOTH offers full and continuous contact, whereas an ACR functions via the 13.5 volts open or closed ability.
I also understand your suggestion of using a switch controlled contactor, rather than an ACR.


I have to add this:
IMO, along with owning and operating boat or RV, comes the need to manage battery banks, water systems, and so on. I bit more complex than climbing into our daily driver, and perhaps not all people are suited to do this.
So with regard to keeping it simple, I fully agree. However, to expect that we can turn on one BS or one MBSS, and go boating....., I think that's a bit unreasonable.
Not that that's what you implied....... Just say'n.


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Woodie, I know that it would require some of your time, but would you be willing to draw up a schematic (or modify my schematic) that shows your preference? I'd be able to see just what it is that you'd change or do differently.
I'd sure be interested to see what you'd do schematically here.


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