Jump to content

Welcome to TheMalibuCrew!

As a guest, you are welcome to poke around and view the majority of the content that we have to offer, but in order to post, search, contact members, and get full use out of the website you will need to Register for an Account. It's free and it's easy, so don't hesitate to join the TheMalibuCrew Family today!

Sign in to follow this  
OLDGUY

Charging different battery banks

Recommended Posts

OLDGUY

I have four batteries in my boat. Two are start/deep cycle hooked in parallel. They are charged by an onboard battery charger when not on the water and charged by the alternator. My other two are deep cycle in parallel. They are charged by on onboard battery charger also. Is there a way to get the alternator to charge these also. Perko switch the only way, switching back and forth between battery banks? 

Share this post


Link to post
MLA

Start by describing the style of switch you have and how its wired. Knowing some more details will help to more accurately answer your question. There are some passive/manual setups. 

Share this post


Link to post
minnmarker

ACR ACR ACR

Install and forget about batteries and switches :)

Share this post


Link to post
OLDGUY

Right now there is no switch. The two deep cycle are for an amp and are only charged by the onboard charger.

What is an ACR?

Share this post


Link to post
MLA

ACR stands for auto combining relay. You should install a dual bank switch and reconfigure the wiring. As to your main question. With traditional 1/2/BOTH/OFF switch, the alternator will contribute to which ever bank you have the switch turned to. Simple yet effective, you just have to have some discipline and not leave it on BOTH when at anchor. 

With the proper switch and ACR, its a little more simple for the operator, but the wiring set up is a little more complex as compared to the traditional switch. With an ACR setup, switch on when you launch the boat, switch off when you put boat away.   

Share this post


Link to post
NHolladay

Get a perko 1,2 all switch and all will charge just run each parallel set as a single unit on 1 and 2 then you can pull from either and charge both banks.

 

Or just parallel all 4 you get the same benefit all the cranking amps and still 12v or NO

Edited by NHolladay

Share this post


Link to post
minnmarker
44 minutes ago, MLA said:

With the proper switch and ACR, its a little more simple for the operator, but the wiring set up is a little more complex as compared to the traditional switch. With an ACR setup, switch on when you launch the boat, switch off when you put boat away.   

Or put an ACR between the banks and don't worry about switches at all.  Unless you have an unusual boat or don't use it for several weeks in a row the parasitic drain will not have a significant effect on the batteries.  https://www.bluesea.com/products/7610/SI-ACR_Automatic_Charging_Relay_-_12_24V_DC_120A

Click on installation with battery charger.  It really is that simple.

Share this post


Link to post
MLA
Just now, minnmarker said:

Or put an ACR between the banks and don't worry about switches at all.  Unless you have an unusual boat or don't use it for several weeks in a row the parasitic drain will not have a significant effect on the batteries.  https://www.bluesea.com/products/7610/SI-ACR_Automatic_Charging_Relay_-_12_24V_DC_120A

Click on installation with battery charger.  It really is that simple.

A few reasons why im not a fan of skipping the manual switch

1) all loads are wired battery direct. its a nice feeling to know that when walk away from the boat slip or park the boat at the storage lot, that ALL electrical loads, minus the bilge pump, are disconnected from the batteries. High current draw devices like amps, still have battery voltage on the terminals, even when the amp is off. A short like from water or moisture, and that amp is drawing current. That can lead to a fire. Off season layup would constitute not using the boat for more than a few weeks. The switch takes car of any parasitic draws from the ACR or any of the boat electronics. 

2) The switch allows for manually combining the banks if needed. This allows for the house bank to assist the main bank in cranking. It also allows the alternator bypass the ACR if the house bank is very low upon refiring the engine. 

3) The switch allows for the batteries to be isolated from each other and for the ACR to be isolated from both batteries when off. This lets the dual bank charger condition and charge each bank independently. 

Share this post


Link to post
minnmarker

All good points MLA, if they apply to a particular setup.  If bilge pump is on the starter battery the amp drain is not a sinking problem, especially if the boat lives on a trailer or lift.  If the starter battery has little or no "floating around" load it'll stay charged no matter what you do to the stereo batteries. So unless there is a good reason to have a switch (and there are some) I would rather not have one more thing to think about during the season - and just pull the negative battery post terminals when storing for the winter.  Keeping It Simple.

Share this post


Link to post
MLA

I can keep it simple. Turning a single switch off seems easier then pulling the covers on batteries and disconnecting the grounds. Only to return months later and have to reconnect. I field about 3-4 calls every spring. House battery goes dead, boat wont start, stereo doesnt work, etc, etc, etc. Its always the same thing. Batteries disconnected in fall and a cable was overlooked in the spring or connected back to the wrong spot. 

With an ACR only setup, how to isolate the banks so the on-board charger does not close the ACR, combine the banks, making them one? This is less than ideal for the batteries when one is dedicated for cranking and the other is dedicated for house loads. 

A work-around for these, is simply fixing what would be an nonissue with a switch. 

Share this post


Link to post
OLDGUY

Thanks for all the information. Ok just so I get this right. I have two battery banks, each has its own onboard battery charger. So in theory when I leave the house all batteries at 100% charge.

So I'm going to order the "add a battery kit" and all four batteries will get charged by the alternator when I'm out on the water? 

Share this post


Link to post
minnmarker

Yep, as long as the engine is running both banks are being charged. When you're sitting with engine off and stereo playing only that bank will be discharging. Easy. Simple.

Share this post


Link to post
Steve B.

This may be a project for me in the off-season as an upgrade. Just to veryify, I can and will use my perko in addition to the ACR ? I could get rid of the perko. But keeping it essentially makes it more versatile?

Thanks,

Steve B.

Share this post


Link to post
formulaben

 

Power Mix.

 

Share this post


Link to post
Nitrousbird
On ‎9‎/‎13‎/‎2016 at 11:43 PM, MLA said:

A few reasons why im not a fan of skipping the manual switch

1) all loads are wired battery direct. its a nice feeling to know that when walk away from the boat slip or park the boat at the storage lot, that ALL electrical loads, minus the bilge pump, are disconnected from the batteries. High current draw devices like amps, still have battery voltage on the terminals, even when the amp is off. A short like from water or moisture, and that amp is drawing current. That can lead to a fire. Off season layup would constitute not using the boat for more than a few weeks. The switch takes car of any parasitic draws from the ACR or any of the boat electronics. 

2) The switch allows for manually combining the banks if needed. This allows for the house bank to assist the main bank in cranking. It also allows the alternator bypass the ACR if the house bank is very low upon refiring the engine. 

3) The switch allows for the batteries to be isolated from each other and for the ACR to be isolated from both batteries when off. This lets the dual bank charger condition and charge each bank independently. 

You can do ALL of this with an ACR.  You can switch the batteries off.  You can combine all of them.  You can isolate the batteries when charging by simply unhooking the ground reference wire on the ACR or adding a relay that opens onto that wire when voltage is applies to your charger (I just pull the ground but both work).  So everything you mentioned is a non-issue with an ACR is wired/used correctly.  ACR is the way to go IMO.

Share this post


Link to post
shawndoggy
2 hours ago, Nitrousbird said:

You can do ALL of this with an ACR.  You can switch the batteries off.  You can combine all of them.  You can isolate the batteries when charging by simply unhooking the ground reference wire on the ACR or adding a relay that opens onto that wire when voltage is applies to your charger (I just pull the ground but both work).  So everything you mentioned is a non-issue with an ACR is wired/used correctly.  ACR is the way to go IMO.

You guys are saying exactly the same thing.  MLA is saying you can manually isolate the batteries with a big red switch.  Nitrous is saying you can manually isolate the batteries by pulling a wire (a caveman sort of switch) or by setting up a relay (an automatic switch that opens and closes based on an input from something else).  

I agree with both of them that isolating is the way to go for charging, and NOT using the diagram that @minnmarker links to because that diagram undoes the whole reason for the ACR which is to keep the banks separate (unless of course you are going to charge the batteries with a VERY powerful shore charger, not a weak 5A batterytender for four batteries... but even then you don't get the benefit of a separate maintenance and conditioning charges for each bank).

Me personally, I'm a big fan of the big red switch method because it also shuts down all other boat systems (other than those that are specifically wired around the switch, as your auto bilge should be, for instance).  It's also easy to use and works as expected (switch off, boat off; switch on, boat on).

Share this post


Link to post
MLA
3 hours ago, Nitrousbird said:

You can switch the batteries off.

Please explain how you do this without a switch

3 hours ago, Nitrousbird said:

You can combine all of them

Which ACR do you suggest that is rated to handle starter current passing through it?

3 hours ago, Nitrousbird said:

You can isolate the batteries when charging by simply unhooking the ground reference wire on the ACR

And what happens if the operator forgets to reconnect the ACR ground at next launch?

 

With one stroke of a manual switch (which may also include an ACR in the mix), I accomplish all of these.  

Share this post


Link to post
minnmarker

Funny how this gets to be such a debate.  We must all be bored.  In any case, I seem to stand (somewhat) alone - but I stand with conviction :rockon:

I have 2 boats with ACRs:

The Malibu is set up with no switches at all, just the ACR between the batteries.  We don't do much if any "floating around draining the stereo battery" in that boat so I'm not really concerned about unequally drained batteries, but I want to be able to start the boat just in case someone leaves the amps on while we're at the bar or they don't see the red light on the amp switch in the sun when leaving the boat at the dock during the day.  I suppose I could put one of the Blue Sea switches in and just leave it in the on position but I don't think it's necessary with the way we use the boat.  There is an on board charger that we rarely use.  It is a single bank and connected to the stereo battery.  One the one occasion we drained the stereo battery down to 12.0 volts and then plugged in the charger, the volt meter on the stereo battery read 13.5 volts right away so I'm pretty sure it was not sucking current thru the ACR from the starting battery.  Comments?  As far as the batteries not being "conditioned," they are rarely on the charger during the summer anyway.  IMHO, no switch, no problem.  During the winter the neg terminals come off and they are on separate smart maintenance delsulfation chargers, the one in the boat and a smaller wall plug type.

The pontoon, on which we do regularly drain down the stereo battery, has the same setup EXCEPT there is a relay on the ACR ground wire which opens when 110V power is supplied to the charger.  This opens the ACR circuit whenever the stereo battery is being charged by the shore charger so the starter battery is not involved at all.  There is a volt meter right by the stereo power switch to tell the state of the stereo battery so we know when we get back to the dock if we need to plug it in or not.  Again, no manual switches, no problem.

No problems with either setup so far and I don't have to worry about anyone turning switches. 

FWIW, I have a hidden switch for power to the ballast pumps to help prevent accidental running (impeller ruining) of ballast pumps if one of the rocker switches on the dash is accidentally pushed.

I suppose I am a bit biased by my past, during which I experienced several problems with battery selector switches being used by un-trained people that resulted in dead batteries or stranded boats...

Share this post


Link to post
shawndoggy
56 minutes ago, minnmarker said:

Funny how this gets to be such a debate.  We must all be bored.  In any case, I seem to stand (somewhat) alone - but I stand with conviction :rockon:

I have 2 boats with ACRs:

The Malibu is set up with no switches at all, just the ACR between the batteries.  We don't do much if any "floating around draining the stereo battery" in that boat so I'm not really concerned about unequally drained batteries, but I want to be able to start the boat just in case someone leaves the amps on while we're at the bar or they don't see the red light on the amp switch in the sun when leaving the boat at the dock during the day.  I suppose I could put one of the Blue Sea switches in and just leave it in the on position but I don't think it's necessary with the way we use the boat.  There is an on board charger that we rarely use.  It is a single bank and connected to the stereo battery.  One the one occasion we drained the stereo battery down to 12.0 volts and then plugged in the charger, the volt meter on the stereo battery read 13.5 volts right away so I'm pretty sure it was not sucking current thru the ACR from the starting battery.  Comments?  As far as the batteries not being "conditioned," they are rarely on the charger during the summer anyway.  IMHO, no switch, no problem.  During the winter the neg terminals come off and they are on separate smart maintenance delsulfation chargers, the one in the boat and a smaller wall plug type.

The pontoon, on which we do regularly drain down the stereo battery, has the same setup EXCEPT there is a relay on the ACR ground wire which opens when 110V power is supplied to the charger.  This opens the ACR circuit whenever the stereo battery is being charged by the shore charger so the starter battery is not involved at all.  There is a volt meter right by the stereo power switch to tell the state of the stereo battery so we know when we get back to the dock if we need to plug it in or not.  Again, no manual switches, no problem.

No problems with either setup so far and I don't have to worry about anyone turning switches. 

FWIW, I have a hidden switch for power to the ballast pumps to help prevent accidental running (impeller ruining) of ballast pumps if one of the rocker switches on the dash is accidentally pushed.

I suppose I am a bit biased by my past, during which I experienced several problems with battery selector switches being used by un-trained people that resulted in dead batteries or stranded boats...

If you have one depeleted battery and one charged battery, the fact that you put a minimal charge (measured in amps) that can get the voltage above the ACR combine threshold (in volts) is exactly the problem.  The ACR combines and the weak battery is going to draw power from the "strong" battery much more quickly that the weak charger can charge both.  

I mean think about it in an extreme example -- you could trick the acr into combining with something as weak as AA batteries.

Your second setup does have a manual switch -- the power cord :)  (totally agree as stated above that that's a reasonable approach)

The "hidden switch" thing tho.... you can do the same thing with that big red power switch I've been mentioning.  It's NOT a battery selector switch, though it also gives you the ability to override the ACR manually.

Edited by shawndoggy

Share this post


Link to post
Nitrousbird
20 hours ago, MLA said:

Please explain how you do this without a switch

Which ACR do you suggest that is rated to handle starter current passing through it?

And what happens if the operator forgets to reconnect the ACR ground at next launch?

 

With one stroke of a manual switch (which may also include an ACR in the mix), I accomplish all of these.  

I misunderstood your post - it sounded like you were for a manual switch WITHOUT ACR (the old 1/2/combine/off switch).  I was referencing the Add-A-Battery ACR setup.  As for the ACR ground, do a relay if it is a concern.  I never turn my battery switch off.

Share this post


Link to post
Kmfish87
1 hour ago, MadMan said:

I never really liked that an ACR combines both batteries together.  I like the idea of my engine start battery always being isolated so I've always used isolators similar to this:

https://www.waytekwire.com/item/80066/Sure-Power-9523A-Mult-Battery/?gclid=CMDbjIehkc8CFdQ9gQodOKEP8g

I guess with this set up you could run a "off-on-combined" switch to still have the emergency starting power of all batteries...seems like a decent idea. Is this isolator rated for marine use?

Share this post


Link to post
shawndoggy
58 minutes ago, MadMan said:

I never really liked that an ACR combines both batteries together.  I like the idea of my engine start battery always being isolated so I've always used isolators similar to this:

https://www.waytekwire.com/item/80066/Sure-Power-9523A-Mult-Battery/?gclid=CMDbjIehkc8CFdQ9gQodOKEP8g

The marine inboard instructions here: http://www.cooperindustries.com/content/dam/public/bussmann/Transportation/Resources/instructions/BUS_CBT_INST_180119a.pdf suggest that AC Delco marine alternators don't have the required battery voltage sense wire?

"NOTE: Be sure that the alternator has remote sense capability. Most single-wire Delco alternators do not have this provision. The voltage regulator must sense battery voltage. The sense line should be connected to the main battery terminal of the Isolator. Call the Sure Power customer-service department if a particular application arises which is not covered."

I thought I also remember that isolators are parasitic (they put out about 3/4 of a volt less than input)?  Can't find a site for that tho so maybe just my memory getting bungled up

FWIW, my combined batteries using blue sea ACR definitely get 14.4v.

Share this post


Link to post
MadMan
46 minutes ago, shawndoggy said:

The marine inboard instructions here: http://www.cooperindustries.com/content/dam/public/bussmann/Transportation/Resources/instructions/BUS_CBT_INST_180119a.pdf suggest that AC Delco marine alternators don't have the required battery voltage sense wire?

"NOTE: Be sure that the alternator has remote sense capability. Most single-wire Delco alternators do not have this provision. The voltage regulator must sense battery voltage. The sense line should be connected to the main battery terminal of the Isolator. Call the Sure Power customer-service department if a particular application arises which is not covered."

I thought I also remember that isolators are parasitic (they put out about 3/4 of a volt less than input)?  Can't find a site for that tho so maybe just my memory getting bungled up

FWIW, my combined batteries using blue sea ACR definitely get 14.4v.

My alternator does have the remote battery sense connection.

51 minutes ago, Kmfish87 said:

I guess with this set up you could run a "off-on-combined" switch to still have the emergency starting power of all batteries...seems like a decent idea. Is this isolator rated for marine use?

I actually removed factory "on-off-combine switch (more connection just give more chance of problems).  My idea is, if I ever need to switch batteries to start the engine, it's just a 3 minute job switching the cables.

 

Share this post


Link to post

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Restore formatting

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

Sign in to follow this  

×
×
  • Create New...