Electrical Systems 101

[Stu Jackson]

Over the past decade or more, "regular" electrical topics come up repeatedly.  In developing responses to questions, many of us use the handy links to earlier discussions.  I've developed this "Electrical 101" topic, which is a group of links to popular subjects and those discussions.   Many of them include links to other websites and message boards, since boat electrical systems are not boat-specific.  Many thanks to Maine Sail, not only for his contributions to this message board, but for his "Musings with Maine Sail" on www.catalinaowners.com: http://forums.catalina.sailboatowners.com/forumdisplay.php?f=135 and his own website:  http://www.pbase.com/mainecruising/boat_projects

You could buy a few good books (see Reply #7 below), or you could read this stuff. Good luck.

**************************************************
**************************************************

Here are some good "intro" courses for Electrical Systems:

The All-Important Energy Budget:

http://c34.org/bbs/index.php/topic,3976.0.html

Record of Daily Energy Use of 100 ah per day:

http://c34.org/bbs/index.php/topic,6353.msg41471.html#msg41471

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

http://c34.org/bbs/index.php/topic,4949.0.html

The Ample Power Primer  http://www.amplepower.com/primer/primer.pdf

OEM 1-2-B Switch Wiring History  http://c34.org/bbs/index.php/topic,4949.msg30101.html#msg30101

Basic Battery System Descriptions (bottom of page one, then to page two)

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

another good discussion, scroll to the top to start:  http://forums.catalina.sailboatowners.com/showthread.php?p=680363&highlight=duo%20charge

Alternator heat, Regulator Controls, Small Engine Mode

http://c34.org/bbs/index.php/topic,4454.0.html

Small Engine Mode - discussion with link to the picture of the toggle switch: http://c34.org/bbs/index.php/topic,4454.msg27149.html#msg27149

Ammeters & Shunts 101: http://c34.org/bbs/index.php/topic,6032.0.html

Breaking in New Wet Cell Batteries:  http://c34.org/bbs/index.php/topic,6353.0.html

Understanding Batteries http://c34.org/bbs/index.php/topic,6488.0.html  with a link to another website

Battery Acceptance by Stu  http://c34.org/bbs/index.php/topic,4787.0.html

Battery Acceptance (a very good Maine Sail presentation and further discussions)   http://forums.catalina.sailboatowners.com/showthread.php?t=114054  

Battery Acceptance Observations by Maine Sail
http://forums.catalina.sailboatowners.com/showthread.php?p=674108&highlight=battery%20acceptance

Overcharging with Combiners or ACRs The MYTH:
http://c34.org/bbs/index.php/topic,7052.0.html

AGM Battery Issues (from Maine Sail)  
http://forums.sbo.sailboatowners.com/showthread.php?t=124973

AGM Battery Issues and the Blue Seas Dual Circuit Switch (from Maine Sail) "DARN AGM Batteries"
http://forums.catalina.sailboatowners.com/showthread.php?p=848465&highlight=darn%20agm

Alternator Regulator Wiring Diagrams  http://c34.org/bbs/index.php/topic,4548.0.html

How Alternators & Regulators Work (by Maine Sail):  http://forums.sbo.sailboatowners.com/showthread.php?t=125392

Basic Battery Wiring Diagrams  This is a very good basic primer for boat system wiring: http://c34.org/bbs/index.php/topic,6604.0.html

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

Golf Cart 6V Battery Wiring  http://c34.org/bbs/index.php/topic,7162.0.html

Stu's Wiring Diagram  http://c34.org/bbs/index.php/topic,4623.msg27335.html#msg27335

Power Share Feature for Link 2000 Controlling Honda Generators
Very helpful hint to control generators and 20A shorepower
http://c34.org/bbs/index.php/topic,1474.0.html

Solar Systems:  Selection, Installation & Controllers by Maine Sail  SUPERB

http://www.pbase.com/mainecruising/solar_panel

How to Wire a Battery Monitor by Maine Sail:  http://forums.catalina.sailboatowners.com/showthread.php?t=125606

Converting a Leece Neville Alternator to External Regulation  by Maine Sail
http://c34.org/bbs/index.php/topic,4879.0.html

Alternator Sources by Maine Sail  (Reply #16)
http://c34.org/bbs/index.php/topic,5686.15.html

Wiring a new charger From Maine Sail:  http://forums.catalina.sailboatowners.com/showthread.php?t=136765

Echo Charger Use Warning from Maine Sail:  http://www.sailnet.com/forums/electrical-systems/72295-xantrex-echo-charger-rant.html

Installing Battery Selector Switches (the "posts" in the back don't physically match with the switch positions on the front)  http://c34.org/bbs/index.php/topic,6911.0.html

removed dates added 7/30/12

[Stu Jackson]

Here's another good one:  http://www.sailnet.com/forums/electrical-systems/70350-battery-bank-design-recommendations.html  It's looong but covers a lot.

It also includes links to some other wiring diagrams that mirror the options we've been presenting over the years.

Another one that includes a few very succinct system descriptions, particularly Reply #4 by Brian, as well as Maine Sail's always cogent discussions:  

http://www.sailnet.com/forums/electrical-systems/71944-advice-needed-2-bank-battery-system-working-one.html

Here's an excerpt from Brian's description summary:

1. Take the alternator output off of the starter and run a new heavy gauge wire to the house bank positive - with a fuse near the battery bank.  Remove the small #10 or #12 wire between the alternator and the starter.

2. Take the shorepower charger's output off the start battery and leave it only on the house battery positive - again fused near the battery. If you have solar panels or a wind gen the output also goes direct to the house bank.

3. Buy either an Echo Charge or an ACR (automatic charge relay) and wire it to the house +, start + and ground. For a single start battery I prefer the Echo Charge. It passes up to 15 amps to the start (aux) battery when a charge current is sensed and stops when the charge current is no longer present. At no time does it parallel the batteries.  [See the Echo Charge Warning in the post right above this one.]

What this does is change your 1/2/both switch to a "use" switch and not a charge switch. It still lets you decide which battery to use for any load but the charging is automatic.

The easiest way to use this system is to use the house bank for everything and keep the auxiliary battery for emergency use. When you arrive on the boat turn the switch to 1 (house I assume) and turn it to off when you leave. Engine starting is easily accomplished by the house bank.

And there is no chance of error.

Added 7/8/11:  And if your echo charger or ACR breaks, then simply use the B position on the switch but ONLY when charging sources are present! !  Backup, backup, backup. Stu

Hawk's Electrical System  http://c34.org/bbs/index.php/topic,6507.0.html  A very interesting discussion of how Tom's system evolved from input from this topic and how he runs his boat - he decided to use his 1-2-B switch instead of an echo charger and has moved his AO to the house bank.  A very nice compromise that works.

The "concept" of using BOTH (except when charging) and to COMBINE a bad bank with a good one is just plain WRONG.  Please, don't do it.

[Stu Jackson]

And another that sometimes links back to the earlier posts:

Engine Starting Issues - that pesky negative ground connection on the engine and that also pesky hidden starter fuse from the start button (look under your alternator)  

http://c34.org/bbs/index.php/topic,5159.0.html

It All Depends on How It's Wired

[Stu Jackson]

One of the most helpful tutorials ever:

http://www.amplepower.com/tech_docs/index.html

Use the Tech tab to download the Ample Power Primer and associated wiring diagrams.

[Stu Jackson]

Wiring & Installing Battery Monitors by Maine Sail

http://forums.catalina.sailboatowners.com/showthread.php?t=125606

and an interesting followup discussion - why ONLY voltmeters can't really tell you much about the state of your batteries

http://forums.catalina.sailboatowners.com/showthread.php?t=132776&page=2

[Stu Jackson]

Another good wiring diagram from Ken Juul, much ike Jim Moe's wiring diagram in the C34 tech wiki

Ken's:
http://www.c34.org/wiki/index.php?title=Wiring_Diagram_with_4_6v_golf_cart_batteries_and_starting_battery_on_Luna_Loca

Jim's:
http://www.c34.org/wiki/index.php?title=Catalina_34_Electrical_System_Upgrade

Link to C34 Tech wiki Electrical:
http://www.c34.org/wiki/index.php?title=Electrical

[Stu Jackson]

Updated C34 Tech wiki basic wiring diagram with echo charger:

http://c34.org/bbs/index.php/topic,6225.0.html

[Stu Jackson]

BOOKS

Every so often folks ask: "What book should I buy to learn electrical stuff about my boat?"

The appropriate answer is: "Depends on how you like to learn."

Go to a chandlery and read a few in person, and start by buying one that you think suits your "level" and is "readable" to you."

A good starting list is provided by West Marine in the their online Advisors (and usually in their catalogs, one of which should be in your house and the other on your boat).

http://www.westmarine.com/webapp/wcs/stores/servlet/WestAdvisorView?langId=-1&storeId=11151&catalogId=10001&page=Recommended-Books-on-Marine-Electrical-Systems

[Stu Jackson]

Important Considerations for AGM Battery Use  (by Maine Sail)

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

[Dave Spencer]

Wow!  What a great post by Maine Sail.  Great observations on acceptance rates depending on which battery is first in the charging chain.

On a slightly different but similar note, Nigel Calder had a good article in this month's (May) Sail magazine on the perils of some of the new high acceptance rate batteries like TPPL (Thin Plate Pure Lead) and Lithium Ion batteries.  I haven't used these (or even researched them) but it looks like great new technology that will greatly reduce charging times for sailor's battery banks.  However, because the batteries can accept such a high charge rate, the alternator is at or near its maximum capacity for a relatively long period resulting in overheating.  Nigel has offered some ideas on how to deal with these high acceptance rate batteries.

Do we have any thoughts or experience on TPPL or Lithium Ion batteries? 

[Stu Jackson]

Dave, not with the new battery technology, but surely with reducing alternator load and heat:

Small Engine Mode (read the link to the hot alternator topic, too)

http://c34.org/bbs/index.php/topic,4669.0.html

[Dave Spencer]

Thanks for the great links Stu. 
I thought that someday I would surely have a question that this group can't answer. Now, I'm not so certain.

 

[Stu Jackson]

Dave, you'll find this is as applicable to AGM batteries as it is to the newer technology.  AGMs have high acceptance rates that can tax even high output alternators.

[Stu Jackson]

For everyone installing a battery monitor:  The "Gotcha Algorithm" thread, a "MUST READ"

http://c34.org/bbs/index.php/topic,4922.0.html

DEFAULTS are factory settings that are made to be modified to suit your setup.

[Stu Jackson]

Engine Start Problems, with a good discussion of various issues.

http://c34.org/bbs/index.php/topic,5159.0.html