Starter Battery Component Locations

[mark_53]

There is also this about that wiring diagram:

PLEASE NOTE for Option 2: The wire from the 2 post of the 1-2-B switch is shown going to the starter; it can also just as easily be run to the lower post of the on/off switch, which is just the other end of the same wire.  The switches are usually closer to each other, resulting in less wiring.

Yes, connecting the wire from the 2 post to the "lower" post (I don't think it matters which side) is a possibility but, on our c34s, that wire is already connected to the starter.  Probably easier to leave it there.

[mark_53]

Mark,

I hear you and I understand.  However, please consider my earlier point about a location for an external regulator, which you MAY come to when you upgrade your alternator.  If you never plan to do that, ignore the rest of this.   

At this time I don't plan on upgrading the alternator.  Most of my "cruising"  is limited to one or two nights on the hook and then to a marina for nice warm heat and shopping for my first mate.

Given the length of the wiring harnesses that come with regulators, that location is just perfect for the regulator, which, too, needs a visual check.  The only other place I've seen folks locate them is in the aft cabin.  Requires drilling holes for the wiring harness, which is in a black flex conduit, plus the "owner provided" wires needed.

If and when I do upgrade the alternator, the voltage regulators I've seen look quite small.  It looks like there is still room under the head sink to install it even with the battery switch and SI ACR located there.

You really don't need to "see" the ACR light, all you have to do is check the second bank battery voltage when you're charging.  I can say this with true conviction, since I located the "idiot light" for my combiner behind the sliding black cover just forward of the galley.  That was 17 years ago, and I find absolutely NO need to ever check the light.  I have a dual battery analog voltmeter PLUS a Link 2000 to check voltages.  I find seeing the regulator far more important.

Stu, In my case, I don't have a link 2000 or dual battery volt meter so an LED for the SI ACR would provide me some comfort in knowing the start battery is receiving it's charge.  I have the stock volt meter on the engine panel and one on the DP.  Maybe time to upgrade to a decent battery voltage monitor, but for now, I was thinking of using the volt meter on the engine panel to monitor the start battery voltage and use the volt meter on the DP to monitor the house bank.  With a dedicated start battery, and for my style of "cruising", precisely monitoring house bank capacity is not important. If I run the house bank down, I start up and recharge or head to the marina.
Just have to figure out how to rewire the volt meter on the engine panel to the start battery.  Any ideas on that?

[Ron Hill]

Mark : You ask how to use the V meter on the engine panel to monitor the starting battery?

EASY  -  Simply run a + and a - wire (#16)  from the starting battery direct to the meter  (after disconnecting the present meter wires !!!!)

OR  - You could wire to a left/right ON momentary switch (to be mounted on the engine panel), so that meter could monitor what it does now and also monitor a new starting battery

A few thoughts

[Ken Juul]

When I added my start battery, I removed the wire from the alternator to the starter post.  Ran the Alternator output to the house bank instead.  Left everything  on the 12B switch as is.  Wired the start battery through a switch to the starter and ground.  When I start the engine I see the voltage drop heating the glow plugs and see the voltage drop when cranking.  I can do with with the 12B in off so I know I am monitoring the start battery.  If the start battery is getting charged thought the ACR, then I know the house bank is also charging.  I do have a Link to monitor the house battery.

[Ekutney]

I am starting from a very basic wiring configuration (single battery bank, older undersized wiring, older dumb charger) and plan to follow much of the "ideas" documented on this site.   I like the idea of relocating the 12B switch as shown in the picture (aft cabin bulkhead).  I assume this means I no longer need the 12B switch in the distribution panel.  Am I correct?

[Ken Juul]

No the 12B switch is still used.  1 is the house, 2 allows starting the engine with the house battery.  The added switch only controls the start battery.  My 12B switch is either off or in the 1 postition to power the house.  The start battery switch is either off or on.

[mark_53]

Left everything  on the 12B switch as is.

Ken:
Your schematic shows the starter cable on the 1-2-B switch on the #2 post.

The factory default for the starter cable is on the "C" post.  I plan on moving the starter cable on the 1-2-B switch to #2 post as shown is mainsails diagram.

[mainesail]

For customers with this set up I simply leave a copy of all the scenarios of switch use on-board. This is what it looks like.. If you use an ACR replace the words Echo Charger with ACR,

NORMAL EVERYDAY USE:

ISOLATED START & HOUSE
Note: Alternator charges HOUSE and Echo Charger charges START.
1/2/ALL = #1
ON/OFF = ON


EMERGENCY SCENARIOS:

START & HOUSE PARALLEL
Note: This overrides the Echo Charger & sends more current to START bank.
1/2/ALL = ALL
ON/OFF = ON

Emergency Situ #1 - START - Provides HOUSE & START Loads:
Note: Use if the HOUSE bank was to fail, for whatever reason. This isolates the HOUSE bank & uses the START bank for everything.
ON/OFF = ON
1/2/ALL = #2

Emergency Situ #2 - HOUSE - Provides HOUSE & START Loads:
Note: Use if the START bank was to fail, for whatever reason. This isolates the START bank & uses the HOUSE bank for everything..
ON/OFF = OFF
1/2/ALL = ALL

[mark_53]

Is there some reason not to put it behind the electrical panel connected directly to the 1-2-B switch? Seems like an easy location- no wires to snake. The ACR shouldn't generate much heat.

This sounds like a good location. 
Advantages:
-Very short jumpers to ACR from house battery and start battery cables
-Uses existing #4 cables,
-Out of sight
-Can run the ACR activity LED to main DC panel.

Disadvantage(s)
The cable run to house and start batteries is a few feet longer than a direct run from house under galley to start battery.
The sensing lead from the ACR to ignition switch may be difficult to route.
But just way to many wires in there to fit it and the cables.

Another option as Stu suggested is the cuby just in front of the port settee seat back.

[Stu Jackson]

The text that Maine Sail provided is already included in the link in Electrical Systems 101:

This is another very good basic primer for boat system wiring:   The 1-2-B Switch by Maine Sail (brings together a lot of what this subject is all about)
http://forums.catalina.sailboatowners.com/showthread.php?t=137615

A shortened version/explanation is included in the earlier 101 link.

[mainesail]

Is there some reason not to put it behind the electrical panel connected directly to the 1-2-B switch? Seems like an easy location- no wires to snake. The ACR shouldn't generate much heat.

This sounds like a good location. 
Advantages:
-Very short jumpers to ACR from house battery and start battery cables
-Uses existing #4 cables,
-Out of sight
-Can run the ACR activity LED to main DC panel.

Disadvantage(s)
The cable run to house and start batteries is a few feet longer than a direct run from house under galley to start battery.
The sensing lead from the ACR to ignition switch may be difficult to route.

If the alternator & other charge sources are properly wired to the house bank then the ACR is passing a few amps or less across it. The proper installation of an ACR, with disparate sized banks, is to the larger house bank first then the ACR charges start.

The SI wire is not really a sensing wire it disables or opens the ACR the second you hit the start button.

Wiring a dedicated start battery is a fine approach but it does not eliminate the potential for transients. The best thing you can do is to properly wire the boat so all loads come off the batteries as close to the batteries as possible. This is one reason I prefer battery switches closer to the bank, as does the ABYC...

I put this together a short time ago..
Voltage Transients In Marine Battery Systems (VIDEO LINK)

[Ken Juul]

Thanks for the correction Mark.  Mine is wired per the diagram.  Been a few years since I did it.....the mind is a terrible thing to lose

[Ekutney]

I am starting from a very basic wiring configuration (single battery bank, older undersized wiring, older dumb charger) and plan to follow much of the "ideas" documented on this site.   I like the idea of relocating the 12B switch as shown in the picture (aft cabin bulkhead).  I assume this means I no longer need the 12B switch in the distribution panel.  Am I correct?

I should have included the picture and worded my question differently.

Do you still have a 12B switch in the power distribution panel or was it moved to the aft cabin as shown in the picture?

[Ekutney]

Redundant but thought it appropriate to add:

I agree 100% that reviewing the 101 link to this subject has all the information required, much of it from Main Sail the SME on the subject.  I especially reference the detailed explanation on the 12B switch:

The text that Maine Sail provided is already included in the link in Electrical Systems 101:

This is another very good basic primer for boat system wiring:   The 1-2-B Switch by Maine Sail (brings together a lot of what this subject is all about)
http://forums.catalina.sailboatowners.com/showthread.php?t=137615

A shortened version/explanation is included in the earlier 101 link.

I struggled over why the placement of the 12B switch but it seems at the time my boat was built (30 years ago it made sense.

I have spent hours reviewing the vast amount of information on this site on a wide variety of subjects, I feel like I am in a library of C34 knowledge.  Thanks again to those that contribute, your efforts are appreciated.

[Ken Juul]

I left the 12B switch on the panel.