Battery Charger Configuration

[Julian Elliott]

Since acquiring my new (to me) 2005 MkII, earlier this year, I have been busy converting it from a floating condo into a proper cruising  boat for Northwestern waters.  I have been amazed at the accumulated knowlege of this list, and have found it extremely helpful in figuring out many things, and look forward to contributing in the future.

Next on my list (after cruising season) is upgrading the DC system to incorporate a starting battery, beefy alternator, etc.  Today, I began to map out the current wiring. and found something curious.  I currently have 2 house banks (4D's), connected as expected to a 1-2-BOTH switch.  Each battery has a wire (approx. 10-12 ga), fused, and going to the OEM Charles 5000SP battery charger, which - according to the documentation- can charge 3 separate banks.

I was surprised to see only one positive red lead (plus a black common) coming out of the DC side of the charger.  Ie, it appears that both battery banks are being charged from a single output.  The installation seems to be undisturbed from the original factory wiring, so it appears this came from Catalina in this configuration. 

Anyone else have this configuration?  Is this a common design practice for Catalina?

Julian Elliott
Tenaya #1713

[Stu Jackson]

Do you have a combiner or echo charger?

[Julian Elliott]

Stu,

I intend to add a combiner relay; today, I have a standard 2 bank system, each charged directly from one output of the Charles. 

A reasonable question, though.  When I add the combiner, I'll only need one output.   I'm primarily stumped why it is set it up this way.   Seems bad for charging 2 banks unevenly.

I guess it's my physics background; I need to understand the theory of "why", not just "how".

[Roc]

In thinking about my set up from the factory (MkII also), I can only say that Catalina connected the two wires to the batteries, but only one of them reaches the charger.  Did you track both wires leading from the battery positives to see if one dead ends somewhere?  If this is the case, then both your batteries would only be charging if your 1-2-both switch is on both.

[John Sheehan]

Julian,

Just checked the wiring on our 2003 and there are separate wires going from the charger to each battery.  The charger has one free slot for a third battery.

John

[Ron Hill]

Julian : I'm not that familiar with a Charles AC powered charger.  However, if it's capable of charging 3 battery banks, you should have a separate positive wire (8 or 10 gage, depending on the length of the wire run) from the charger to each of your batteries.  The common negative wire would be connected to the negative post on the furthest "down stream" negative battery post.

Seems that you should also be able to add a starting battery to that charger if you don't have an Echo charger.  Just make sure that all of the batteries are of the same type.  

[Bill Asbury]

Julian, we also acquired a 2005 C34 this year with the same setup you have---Charles 30A 5000 SP Series and two 4D batteries undisturbed since commissioned in 6/04 and no problems so far.  Had four Trojan T-105s in house bank plus separate starting battery on previous '91 C34 which worked well and plan to change over to this setup on the new (to us) boat in due course.
Bill

[Julian Elliott]

Thanks fpr the comments.  I've diagrammed out my DC system fully, and except for that charger anomoly, all wires are "spoken for", altho I had to reroute my Espar furnace directly to the battery.   Re the charger, I'll just accept the system as is for now.  This does need correction, however.

As an aside, my previous 1996 C320 had a separate 4-guage alternator charge wire from the engine to the combo switch.  Unless I'm mistaken, it now seems the starter 2-guage wire does double duty and energizes the starter, plus sends amps back to the batteries when the engine is running.  Money-saving I guess; haven't thought thru yet whether this is suboptimal, and what this means to my upgrade.  Next project....

[Ken Juul]

the echo charger or combiner relay is used with the alternator not the charles charger.  Allows the alternator output to go to the house bank, and when needed charger a second battery.

[mainesail]

the echo charger or combiner relay is used with the alternator not the charles charger.  Allows the alternator output to go to the house bank, and when needed charger a second battery.

Not necessarily they can be used with solar, wind, battery charger or alternator. Any charging source will work with VSR/ACR's or an Echo type charger. I had a Charles charger on my 2005 C-310 using one output and a VSR.

This is from Yandina the folks who invented the Voltage Sensitive Combining Relay:

BATTERY CHARGERS
A single output shore power charger can be directly connected to the house battery. When it is charging, the
Combiner(s) will share the charge with the other banks. Multibank chargers can be connected to each of the battery banks
as normal. Inverters with integral chargers will automatically charge the house bank and it will share the charge to the starting bank(s) through the Combiner 150.

You can do it either way, but.... The problem with some multi-output chargers is that when connected to more than one bank they limit the output on all banks to the max of the unit. So if your charger that is rated at 20 amps total and is charging a start bank that did not need the full ten amps, perhaps only 1/2 an amp, from output #2, the house bank still only gets a max of 10 amps. This is the case on a few of the chargers out there and is not always published well in the manuals. 

I personally prefer the simplicity of a single output charger, like the Iota's, and then an ACR or Echo to maintain all banks. I have wired many systems with a single output charger to the house bank and then used the Echo or VSR/ACR to charge both banks from the house it is simple & easy and requires less fuses. If you have an ACR or Echo fitted you would fine to use a single output on the charger run directly to the house bank. The Echo for example does not work in reverse and is a one way device so needs to be used with a single output device feeding the house bank.. 

[Stu Jackson]

Maine Sail's right.  A search on "single output charger" gets these threads:

http://c34.org/bbs/index.php/topic,1208.0.html

http://c34.org/bbs/index.php/topic,1132.0.html

I'll betcha that if you did a search on "single output" you'd find more.

[Stu Jackson]

We get into details here, bottom of page 1, most of page 2.  Links galore!   Back here, mostly...

http://forums.catalina.sailboatowners.com/showthread.php?t=104505