Wiring a Blue Seas ACR

[warthog5]

Some of you may have seen this posted on other forum's?

There always seems to be question's on wiring and the level of knowledge is unknown by the person asking the question's. So in the interest of a pix is worth a 1000 word's.

 I've had request's for a drawing.

Well I finally sat down with my nifty software and drew it out.

[John Jones]

Thanks!

Looks good.  Thank you for using on/off switches instead of the normal 1,2,both, off switches.  

I wired my boat basically the same except that I have a third auxillary battery that I can switch to either house use or cranking use.  I haven't sprung for the ACR yet but it's on the list.  All four switched to ON puts all three batteries in parallel.

Oh yeah, I have a 3 bank 5A per bank charger that stays plugged in 24/7 if not on the water.

simple drawing without fuses, CBs, etc.

[RickK]

I think you've done a great job in everything except explaining what an ACR is.  Done a search and still have no clue.  Some kind of regulator?

[John Jones]

http://www.bluesea.com/product.asp?Product_id=53476

When the crank battery is fully charged, it starts charging the second battery.

IMHO Blue Sea makes the best marine electrical products without being outrageously expensive.

[RickK]

But it's not a battery charger - distributes the charging from the motor?
ACR - Automatic Charging Relay.
Saves the alternator in the motor I guess - especially when you have your A+B switch to both.

[John Jones]

It ensures the cranking battery gets priority charging, then charges the second battery when the cranking battery is fully charged.  All from the motor alternator.

AB switches will get you in trouble sooner or later.

[warthog5]

Saves the alternator in the motor I guess - especially when you have your A+B switch to both.

Running in Both is a bad idea. Here's why. Buy the way that is known as putting both batteries in Parallel.

If one battery devolop's a shorted cell. The good battery will discharge into the bad battery trying to equalize both of them.

The result is 2 dead batteries.

Here's another reason. You have motored out to your favorite sand bar. the radio has played for hour's. This is another reason I hate high powered amp's. They consume mass quanities of amp's and KILL batteries.

Any way you didn't turn the switch back to 1 or 2 and now your motor will not start due to 2 dead batteries.

The ACR has circuitry in it that parallels the batteries as long as there is not a load put on one of the batteries. If a load is sensed it open the circuit automatically and the batteries are no longer in parallel. This save's one battery to crank the motor.

It charges both batteries from one alt. 2 batteries are not only a good back up, but now your electronics get powered by the house battery. This stop's from spiking your electronics when cranking the motor.    

It's a win, win deal.

[RickK]

I have always heard that the "both" is used to start your engine in critical times and that most alternators are not designed to charge both batteries at one time, so don't leave it in "both" after starting.  If you leave the switch in "both", trying to charge both batteries at the same time, you could damage your alternator.  Looks like the ACR will prevent charging both at the same time, thus protecting your alternator - at least one of the things it does.
BoatUS=$95.

Another item for our "Resources" section

[John Jones]

That's basically correct on the "Both" setting.  Another issue is that a battery that is going bad will drain the good battery if you forget to put the switch back to normal.  In my experience, most people put the switch in Both and leave it there forever.  My main issue is that my old brain has enough to remember without adding one more thing to the list.


My third battery saved my last fishing trip.  With the boat in the water, tied to the dock with the motor running, I started turning on electronics.  VHF - ok, GPS - ok, Furuno 582 fishfinder - "beep" with a black screen  :(
My first thought was that my high dollar bottom machine had died.  Then I looked at the GPS and it was showing 9.6 volts     I turned everything off, switched the house battery to OFF and turned ON the AUX 2 switch in my drawing.  12.6 volts to my electronics as it should be.  We were able to make the trip and worry about the bad battery the next day.  The bad battery was three and one-half years old so it was past due and I had been expecting it to die anyway.

[JimCt]

This is a real interesting thread.  Have been sitting back listening to the back & forth.  Will be starting from scratch with the 240 so options are open.

[RickK]

I am going through the 230 now and I know a couple things:
1) The batteries were purchased 4/06 (sticker on side of both)
2) I don't have a whole lot of room in the starboard storage box - has 2 batteries in it and of course, no room to work. Normal  
3) The previous owner mounted an A-B-Both switch THROUGH THE SIDE OF THE BOAT :cry:  instead of mounting a backing board. Look at the 4 bolts behind the Aquasport emblem:

4) I need at least a dual bank charger - just purchased one for the 170.
5) I see the fused red feed to the ACC panel and it doesn't look too heavy - like 16 or maybe 14 - so that has to be replaced.  Luckily I don't have a bunch of electronics or a searchlight on the ACC panel to really draw - yet.
5) Probably should install the parts shown in this thread.  Lookin' at about $225 just for the blue sea stuff - gotta add all the heavy wire too.

[warthog5]

One thing I do believe in is heavy wire/cable and higher end batteries. It cost's you up front, but pay's for itself down the road.

I build extra into a system, because you don't know what you will add 2yrs down the road. I want to be able to just hook it up and not be undersize on my cabling.

I look at a guy's boat the other day that was being reworked. I asked about the size cable he was going to run?

He said about that big, as he mde a little circle with his finger's.

I said that doesn't tell me s#*t. What gage?

he said I have it right here. Ok let me see it.
He bring's out this old cable that was in the boat before. Non tinned, no shrink tubing on the terminal's, corrosion  and stiff as hell.


He said well I don't have the money to buy new stuff. I told him I wouldn't put that in my or anyone else's boat. It may work, but why install a headache for down the road?

[RickK]

I was in BoatUS tonight and read the back of the ACR package and it said that it closed both contacts while charging, opens one when under load.  A little different than what we thought - I guess it's like a newer version of a battery isolator?

[RickK]

This is a real interesting thread.  Have been sitting back listening to the back & forth.  Will be starting from scratch with the 240 so options are open.

I agree - I found everything listed at BoatUS but it ain't gonna be cheap.  If you find better sources, let me know. I'd definitely lay it out on a backer board before you glass or 5200 that in so it'll be easy to work on.  I'll have to take muscle relaxers BEFORE I start trying to contort my body into the storage locker where everything is  

[GoneFission]

Here's an approach from the RV world that is worth looking at:

http://www.intellitec.com/pdfs/BATTERY_ ... 62.000.pdf

Intellitec is a division of General Dynamics, and has a great reputation for quality products.  The BIRD is not waterproof and would need to be mounted somewhere that is not exposed to direct water splash - think about maybe where you would mount a battery charger - and put this nearby...