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tomlarkin
01-04-2010, 11:12 AM
I'm sure this has been discussed here before, but nothing comes up on a search...

I'm at the point of installing my house and starter batteries and want to be sure to do it right. I have the Calder and Casey books, which explain the theory well enough, but I want a more cookbook-style approach: use this size wire and these fittings, attached this way. They also don't discuss applicable ABCY specifications, which I want to follow exactly.

For instance, here's (http://www.pbase.com/bartenderdave/image/88972470) a great build that shows a battery install. There are details in this picture that aren't described in the books I've seen.

Basically: what book or books do I need to design and install my DC system safely and to code? Thanks!

botebum
01-04-2010, 11:24 AM
Doesn't the Calder book break it down fairly well? My copy is buried away in a box in the shed and I haven't opened it in literally years so I don't recall. This one. (http://www.woodenboatstore.com/Boatowners-Mechanical-Electrical-Manual/productinfo/300-268/)

Doug

donsmarine
01-04-2010, 12:03 PM
Get a copy of the ANCOR wire catolog,copy of BLUESEA switch catolog,and vent the battery to open air better than the picture is,althou it's not terrible. Batteries produce hydrogen gas while charging which is very explosive.

JimConlin
01-04-2010, 12:04 PM
Boatowner's Illustrated Handbook of Wiring by Charlie Wing

Boatowner's Mechanical and Electrical Manual by Nigel Calder

George Ray
01-04-2010, 01:51 PM
Not a cookbook but my favorite DC marine electrical book, it appears simplistic but I find it explains basic principles better than other sources. It is always my first 'go to' DC electrical book. Think it's out of print so that may make the scanned-pdf ok?

The 12volt Doctor's Handbook - (.pdf download)
http://www.motoren.ath.cx/download.php?filename=_electrical/12volthandbook.pdf

***********
Opps! guess it's still in print .. if you download it and like it you should do what ever you think is the right thing.
http://www.amazon.com/12-Volt-Doctors-Practical-Handbook/dp/187879700X

RodB
01-04-2010, 02:01 PM
Besides the Charlie Wing book, which is great, the following are also very good...

"Powerboater's Guide to Electrical Systems", second edition by
Ed Sherman

"Sailboat Electrics Simplified" by Don Casey

If you decide to get a bit more involved in diagnosing etc. the following is really good...

Ed Sherman's "Advanced Marine Electrics and Electronics
Troubleshooting"

Once you get the gist of most of the basics, its a matter of drawing your own wiring diagram for your boat. All these books show pretty much how to make connections, wire gauges, etc. The Wing book and the first Sherman book are must haves in my opinion.

Heres the diagram I drew up for my own boat. Once you draw up the basic wiring diagram for your boat, you can also make a sketch of the boat and show locations of electrical elements with as much detail as you want. On how to set up your electrical system, its really getting the basic parameters of the wiring gauge to use, circuit breakers, switches, fuses, buses, etc and then putting the pieces together in the framework of your boat. . . with each run of wire selected to meet its own amps requirement with circuit breakers and fuses protecting the circuits. Use tinned wire, ancor connectors, and shrink wrap as shown in the books above.

RodB

http://i40.photobucket.com/albums/e239/Prestoboat/ElectricaldiagramTexFlatsBoat-72.jpg

AstoriaDave
01-04-2010, 02:40 PM
For instance, here's (http://www.pbase.com/bartenderdave/image/88972470) a great build that shows a battery install. There are details in this picture that aren't described in the books I've seen. Basically: what book or books do I need to design and install my DC system safely and to code? Thanks!Sheesh. Thanks, Tom, for the compliment. As a new guy to all of this, I just followed a more experienced guy's footsteps. Others have chimed in with Nigel Calder's tome, which is very good, and what I would have followed if I had had it when I did my electrical system.

Ventilation of the battery box to the outside of the hull is stipulated by the USCG (and AYBC-recommended). My vent hose is only 5/16 ID (basically fuel hose), so that perhaps the other fellow who feels the box needs more ventilation is correct. I doubt that, but using a larger ID hose might be a good idea. I think if a person were really trying to improve on a single vent line, two would be better, one for incoming air, and one for outgoing air. |That would be a lot of work. BTW, that plywood box I made does not seal well at the top. If I were to redo it, I'd probably go with one of the pre-made plastic (shudder!) units.

There is a list of USCG-requirements which is somewhere around here, but it is a bit harder to pull information out of than Calder.

Try this: http://tinyurl.com/yd4ft6m You can fish around and get stuff on fuel systems, also, by going here: http://tinyurl.com/ycw3woz

A ratcheting crimper is a very good investment, and it will give you enormous peace of mine to use only marine grade adhesive-lined shrink-tubing equipped terminations. For the mongo cables, you can often get the terminations crimped at a cooperative marine supply store (Fisheries might do it where you are), or there are some low-cost deals that can be used in a vise. Again, check with Fisheries Supply. Englund Marine has their big store here, so I just had them do mine, but Astoria is a long ways for you!

tomlarkin
01-04-2010, 04:34 PM
AstoriaDave - I've spent hours looking at your pictures over the past few years, stealing all your good ideas :-)

Everyone else - thanks for all the good ideas - I'll have to wait until after work to check the links. Work is such an inconvenience!

paladin
01-04-2010, 05:51 PM
First...check all the circuits that will be on each switch...record the current required, then double or tripe it.....measure the runs from the battery, to the switches, to the device to be powered.....then check the appropriate wire size....as I said, triple what you come up with then add 10%. Crimp all connections, used tinned marine wire only, apply solder only to the spade/fork terminal and the exposed end of the wire, use at least 2 layers of heat shrink tubing, get it form digi-key and it will be a helluva lot cheaper than waste marine or similar places. If you need to buy switches...check and or google a site for NKK switches as they make sealed ones and you can purchase splashproof boots for the toggles.

Tom Lathrop
01-04-2010, 06:08 PM
I like Charlie Wing's book for amateurs doing boat wiring.

One item on the diagram shown. It is good practice to put a fuse or breaker on the mains near the battery. Otherwise there may be, and usually is, a long run of wire with full battery capacity behind it that is unprotected. Not a good thing.

AstoriaDave
01-04-2010, 07:55 PM
One item on the diagram shown. It is good practice to put a fuse or breaker on the mains near the battery. Otherwise there may be, and usually is, a long run of wire with full battery capacity behind it that is unprotected. Not a good thing.Amen. I believe the usual rule (USCG? AYBC?) is seven inches of wire or less before you have a mains fuse/breaker. I "discovered" this rule after I had already completed my wiring. Lead to some backtracking. These dealies are good in a tight space: http://bluesea.com/productline/overview/127

Here's one installed: http://www.pbase.com/bartenderdave/image/88972470

RodB
01-04-2010, 09:00 PM
One item on the diagram shown. It is good practice to put a fuse or breaker on the mains near the battery. Otherwise there may be, and usually is, a long run of wire with full battery capacity behind it that is unprotected. Not a good thing.

Yes, Tom I did put a large fuse very close to the batteries and have not gone back to correct my drawing. I should have fixed it before posting it.. sorry.

RodB

Lew Barrett
01-04-2010, 09:05 PM
Tom,

As you live in Seattle, you must go to Captain's Nautical Supply on 15th Ave (Interbay) or to Armchair Sailor on Westlake. Both places have all the books recommended here, including Calder, Sherman, etc.

Pick one or two that you connect to best and make the most out of your shopping spree by going upstairs while at Captains and admiring the wonderful display of binoculars and telescopes.

Both shops are excellent, but I tend to favor Captain's Nautical because
1. They are in my 'hood
2. It is always staffed by friendly old guys you can ask questions to and from whom you will get good answers
3. It has a more varied jumble of merchandise.

But either store will do, and both should be on your resources list if you are a boater in Seattle.

Good luck!

tomlarkin
01-04-2010, 11:02 PM
Lew, I've driven past Captain's a thousand times. I used to live in Ballard. I never went in because from their sign it looks like all they do is telescopes and compasses. I see a long lunch in my near future.

RodB - I've started a wiring diagram. That's what got me so nervous. I was having trouble translating it to real life. The books I have seem to gloss over critical details like size of vent hose and type of blower.

I'm pretty sure I'll get the Charlie Wing book. He seems to talk a lot about ABYC rules. I need to get a surveyor to look at the boat as a prelude to getting insurance. I want it to meet all the regs first try if possible (and also maybe not blow mayself up).

I bought a bunch of wire scraps from Fisheries last week and a nice ratcheting crimper from an auto-supply store. I practiced for a few hours crimping and heat-shrinking, so I feel pretty good about that. Fisheries does have a crimper I can borrow for the battery cables. I can make the connections in the parking lot on my tailgate.

Chuck, are you really recommending two layers of heat-shrink? I've never seen that suggested before. I'm using the tube with glue inside, and it seems incredibly waterproof and solid. The glue squirts out after shrinking. I agree with you on oversizing the wire. It seems like cheap insurance. Do you buy all the different wire colors or rely on good labeling and colored tape at the ends?

Thanks again all!