Alternator/Batteries & "The Basic" 1-2-B Switch BEST Wiring Diagrams

[GORLOFSKY]

Just purchased a 2000 Catalina 34 and I can't figure out the electric system. It was redone by Jack Rabbit Marine in 2006. The reason for the rewire was to separate the house bank from the starting battery, but when there is a load on the house, the starter battery is draining too. My problem is I can't seem to track where the alternator comes in to re-power the batteries. Where does this connect with the batteries in the setup from Catalina.

Any help will be greatly appreciated.

Gary Orlofsky

[BillG]

Before they went bankrupt, Jack Rabbit Marine were a pretty reliable outfit with fantastic customer support.
i would look to see if there is a  Balmar Duo Charger or some sort of battery combiner between the house bank
and starting bank.  This allows the current to move in one direction(to charge the starting battery) but not the other way.
The wires that run from the house bank to the Duo Charge don't have to be as hefty as those from the alternator and therefore may have been overlooked by you when tracing the wires.  If you don't have some sort of battery combiner between the two, then you need to get one.
Lastly, with a Duo Charger, there would be no wire directly from the alternator to the starting bank, current runs to the house bank, then to the Duo Charger and then to the start battery

[GORLOFSKY]

Instead of the Duo Charger I have a Xantrex Echo Charger. It would make the most sense to run the Alternator direct to the house bank, but that does not seem to be what was done. It appears the starter bank is the one being charged by the alternator, but I can't find any alternator wire leading to the starter battery or the selector switch. Where else could the alternator be hooked into to cause this???

Gary

[Stu Jackson]

Gary,

Given your description, we're ONLY guessing here.  What you NEED to do is either find or make a wiring diagram and post it (like I did, reply #23 here: http://c34.org/bbs/index.php/topic,4623.15.html )  That's the ONLY way we can help.

Another post is this one: http://c34.org/bbs/index.php/topic,4934.0.html

I used to joke that we can't help much on this message board with sounds and smells.  Appears that wiring diagrams are pretty much the same.   If I was close to you I'd come by and help you trace wires, but...

Keep us posted, we'd love to help.

[BillG]

The Xantrex and Balmar are similar in nature, and I believe that both recommend that the house bank is first in line for charging then connected to the
appropriate battery combiner and then the starting battery.  If the house bank is excessively low then the Xantrex or Balmar will prevent the starting battery
from being charged until the house bank has come up to a set minimum charge.

Do you have the stock alternator or an upgrade?

Stu is right, you need to do a wire diagram, the alternator wire has to go somewhere.

[GORLOFSKY]

Bill,
The alternator is original and I have a diagram for the wiring. Although I do not have it with me to post, I have looked at it enough to know where everything is on the diagram. The problem is what is on the diagram is not what is actually set up. It shows the alternator leading into the house positive wire and I cannot find this anywhere. I have a positive bus bar and a negative bus bar. The alternator does not go to either of these (not that the positive should lead to the neg. bar). It does not go to the 1-2- both switch by itself either. It defiantly goes to the engine starting positive through the engine on off switch. Can the alternator  somehow be routed to charge back through the engine positive line???

[Stu Jackson]

...and I have a diagram for the wiring. ...what is on the diagram is not what is actually set up. It shows the alternator leading into the house positive wire and I cannot find this anywhere. I have a positive bus bar and a negative bus bar. The alternator does not go to either of these (not that the positive should lead to the neg. bar). It does not go to the 1-2- both switch by itself either. It defiantly goes to the engine starting positive through the engine on off switch. Can the alternator  somehow be routed to charge back through the engine positive line???

Gary,

Your nomenclature leaves me perplexed. 

"Engine starting positive"  What does this mean?

"engine positive line"  Same question.

"...the house positive wire..."  Same question.

and " engine on off switch"  Is this the 12B switch or a separate switch that was installed by the PO and/or Jack Rabbit or an I/O one underneath the nav station seat that is not from the factory based on the manual wiring diagram?

It would be of great assistance to us to help you if you could explain to us what these unfamiliar terms mean.

If it was my boat (& I had to do it on mine), what I'd do is find out two important basic things:

1.  Where the input for charging comes from (forgetting shorepower for the moment, just the alternator) - start at the battery box and work outwards, and follow to, hopefully, the alternator output.  There is only one alternator output and the wire has to go somewhere.  Where does it go?  Only you can tell us because we can't see it from here.  Find out if they ever meet.  I understand that your entire topic is about this very issue, and you're trying to do this, but unless I'm with you on your boat, I can't trace any wires for you from my computer at my desk here in my office.  Plus, what you've described bears no relationship to any basic factory wiring or "usual suspects" for "traditional" upgrades.  Combined with your unusual definitions, there's nothing that "rings a bell" or that gives me an "aha" moment.  You have a system that's been worked on or over with incorrect documentation.  Only you can trace the wiring. 

2.  Document and tell us what happens at your 1-2-B switch connections, and tell us what's there.  In the links I provided earlier, there were two different OEM ways to do it:  one wire off the C post to the alternator and then a small wire to the starter; two wires off the C post, one to the alternator the other to the starter.  Or the alternator output could go to the house bank post on the switch.  We have NO idea what's there now on your boat. 

Without a description of what you do have, regardless of what your wiring diagram says and what you see, which are different, there's no way we can do anything from here to help you, as much as we'd like to.

Can you describe what steps you take to start your engine, and run your house batteries?  Like "Start engine on switch position 1, shut engine down, switch to position 2, etc..." 

Do you have a separate switch for the engine (start) and a separate switch for the house bank?

I understand and agree with your earlier post about the echo charger.  And you wrote: "It appears the starter bank is the one being charged by the alternator, but I can't find any alternator wire leading to the starter battery or the selector switch. Where else could the alternator be hooked into to cause this???"  Only place I can think of is to an ammeter in the engine cockpit panel. 

Do you have a voltmeter or ammeter in the cockpit engine panel?

Essentially, you've told us you have a problem, discussed that your documentation doesn't match what's there, used terms that don't seem to apply to anything I've ever heard about boat electrical systems, and told us you don't know what is there.  How can we help with that limited information? 

I love playing electrical detective, as folks here will attest, Gary, but it sure is hard playin' detective without a body to examine.

In your first post you asked: "Where does this connect with the batteries in the setup from Catalina."  Go to C34 Home at the upper left corner of the main message board screen, use the left hand index and scroll down to manuals.  Read away.

PS -- Where is your boat?  Please see this ID topic: http://c34.org/bbs/index.php/topic,1506.0.html  It's the first one on the MB.

[Ken Juul]

just thinking out of the box here to help with your troubleshooting.  I am not sure this would even work and certainly not recommending this. 

Could your alternator lead be routed to the + post on the starter so it "back" feeds the batteries thru the starter cable?

[Stu Jackson]

Ken, good idea.  The "old" OEM way of connecting the alternator wire that goes from the C post of the 1-2-B switch to the alternator and then on to the starter with the little orange wire could have been employed here in reverse.  Start bank to starter to alternator to C post.  Hmm, weird, but possible.  Still need to address where the house bank went or goes!      If Gary was around somewhere close, I know you and I would have a lovely time ripping his boat apart and finding the answers!   

[GORLOFSKY]

Stu and Ken,

I'm from Connecticut so I'm a just a little far away. When I go down to the boat this weekend I will have to check Ken's thought of "back feeding". I'll let you know what I find.

Thanks for all the help so far.

Gary

[steve stoneback]

Let me start by saying I am electrically challenged..... but I am trying to learn, thanks to this MB. I think my alternator output goes to the + post on the starter.  My starter cable from the 1-2-B switch is fed based on switch position, so aren't which batteries receiving the charges based on my switch position?  Position 1 (starting/reserve) is a single group 27. Position 2 (house bank) is 3 deep cycle group 27's.  In other words backfeeding does work.

I plan on changing my setup to 4 six volt golf cart batteries and a reserve battery.  When I do, I will be running the alternator output directly to the house bank.

Steve

[Stu Jackson]

...my alternator output goes to the + post on the starter.  My starter cable from the 1-2-B switch is fed based on switch position, so aren't which batteries receiving the charges based on my switch position?  

Yes, Steve, you are correct.  That's the rambling, ongoing points that I've been having here in my discussions about the 1-2-B switch.  Because the output of the alternator wired that way, once the engine starts, goes through the switch, the switch position does exactly that.

HERE'S HOW THE OEM WIRING ORIGINALLY WORKED AND WHY YOU SHOULD CHANGE IT

In the diagrams below, please change B to C.  B is a position on the switch, it is NOT a point of wiring connection.  There are three "posts" on the back of the switch: 1, 2 AND C.  There are four positions on the switch: OFF, 1, 2 and BOTH. Thanks.

Figs. 1 & 2 show factory wiring (B1 is the house bank, B2 is the reserve bank).  Sometimes they wired the switch with two wires (which is how my boat was wired in 1986, or the PO could well have had someone add the second wire - doesn't matter to this discussion). Either later on or around the same time, they reduced it to one wire with a little connector between the alternator output and the starter (Fig. 2)  Why?  It was cheaper to build.  That one big wire served two purposes:  when starting it took power from the (selected) battery-or (ies) and fed it TO the starter, and through the small wire between the AO and the starter (small wire, short distance, high current, short time period of current flow); once the engine was running, the small wire did nothing, but the AO started flowing current BACK from the alternator to the switch in the opposite direction.  Same wire, current flowed in a different direction.

It was a very functional and cost efficient design, because it used one wire to do two two things.  "Gee, how nifty!," you say.  

'Cept for a few things:  

The switch determined which bank got charged when the alternator was charging (engine running).  For years people incorrectly thought they had to start on B because they "needed" the power of two banks.  Wrong. And still wrong.  In "the olden days" two equal banks were the design norm.  People would switch daily between one and two for house use.  In fact, new boats still come that way, don't they?  Who says the "good old days" are gone?!

When people mistakenly either moved the switch with poor contacts or the brother-in-law turned the switch off with the engine running, the diodes on the alternator fried.  Why?  Because the output of the alternator was interrupted.  (We discussed this years ago and sometimes with full batteries that won't happen, but it did and still does and is an expensive "maybe" to mess with, when you don't ever have to).

With new higher output alternators, the OEM #4 wiring became too small based on voltage drop, so you were losing charging power, just when you needed it the most: to charge a depleted house bank after a night or two on the hook.

Fig. 3 shows the "preferred" design.  This way, AO always goes to the house bank, which needs it more than the reserve bank ever does, and you can even turn the switch to OFF with the engine and alternator running because the AO is always directly connected to a load (battery).  PDP is the post to collect all wiring going to the house bank (positive distribution post --- to avoid loading up a lot of wires on the battery post - some use a bus bar, I used a Power Post Plus).

The switch then simply does one thing and one thing only:  determines which bank provides power for DC loads on the boat, which are starting the engine and running the DP (distribution panel - your electrical panel with the DC loads).

And it does it very well.  That's why I continue to "defend" the simple 1-2-B switch.

Since the reserve bank hardly ever needs a "big" charge, because it only uses a few amps to both energize the glow plugs and start the engine, and the house bank is perfectly capable of starting the engine, we leave our switch on #1 (house) all the time.  The reserve bank is just that: emergency, backup, reserve.  Not "start."  Many like to use the reserve bank to always start their engines.  That's fine, but is merely an operational issue, rather than a switching issue, because with one 1-2-B switch, with the Fig. 3 "preferred" wiring, you can use the 1-2-B on #2 to start the engine and leave it there until you shut your engine off, because the alternator output is still going to the house bank, always.

A search on the phrase "In Defense" or an advanced search on "1-2-B" with my name will pop up many earlier discussions on this topic.

Also, Steve, between now and when you change your batteries, you can functionally do this by simply moving the AO from the C post on your 1-2-B switch to the house bank post, and install your echo charger now.  This gets the AO off the C post and always goes to the house bank.  If you've already installed a high output alternator, I wouldn't do this now because the OEM #4 wiring between the banks and the switch would be too small, but with the OEM alternator it'd be fine.  This works only with the Fig. 1 wiring, 'cuz if you did it with the Fig. 2 wiring the starter wouldn't work on switch position 2, the reserve bank.  See the Alternator Output and Battery Switch topic: http://c34.org/bbs/index.php/topic,4934.0.html  I edited this topic accordingly.

Another discussion of this issue is on the co.com 'site, here, bottom of page one starts that discussion and moves onto page 2:  http://forums.catalina.sailboatowners.com/showthread.php?t=104505

In the diagrams below, please change B to C.  B is a position on the switch, it is NOT a point of wiring connection.  There are three "posts" on the back of the switch: 1, 2 AND C.  There are four positions on the switch: OFF, 1, 2 and BOTH. Thanks.

[DaveM]

Check this setup out and see if you see a problem.  Maybe I am repeating one of Stu's setups?  It seems to address Alternator always connected and you can get to each battery independently for starting, or combined.  If there is a problem it would be when it is on both so the combining relay and switch would be in parallel.  Don't know if that would give the combining relay any trouble or not.  What y'all think?

Good Winds
DaveM

[Stu Jackson]

That's perfect, and just what we have.  The combining relay and B is not a problem, ever, even if they are both on at the same time.  I don't use B anyway, the relay does that when charging.  B is great for if the relay fails.  "B" is for "Backup"   

Only changes I'd make:  1) call it reserve not start bank;  2) make the house bank #1 because if you ever install a Link 2000 the house bank has to be #1 for "programming" operational reasons.

[DaveM]

Stu  Thanks

Then given that, all we would have to do after doing the wiring harness upgrade is put a combiner in and, instead of running a large hot wire from the Alternator to the Starter terminal to replace the old orange wire, we run the hot wire from the Alternator to the positive of the house bank.   This is of course given that you have a normal old OEM setup with 1-2-Both switch to begin with.  Make sense?

Good Winds
DaveM