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Hey y'all,
I'm pondering the remains of what was once a 12V system on my Catalina 22. Here's a schematic I've come up with off the top of my head for the new system. Can y'all take a look at it for me and let me know if I've made any bonehead mistakes? Any better ways to do it than I'm planning? Also, is there any real advantage of a circuit breaker vs. a fuse, aside from the ability to reset the breaker?
Wire sizes are off the cuff so far and I don't have fuse values because I'm not sure on the power usage of all the loads (I don't own some of them yet :-). Any suggestions in this area would be grand.
It's helpful to standardize your wire size as much as possible, barring things that might have more significant loads. But in your case, there's no need for anything over 14 AWG; I'd use 14 for all runs, other than the main feeds. 8AWG is overkill on your boat for connecting your panel to the power source, but that's OK if you want. Better too big than too small. But all the fixtures you've indicated in your schematic don't draw significant loads, so your overall loading is quite small even if everything were turned on at the same time.
The main advantage to standardizing wire size and color is that you can buy in larger quantities, which is significantly more economical. For example, I see that it appears you've spec'd the ABYC wire color codes, which is commendable, but from a practical standpoint it's completely unnecessary, all the more so in such a straightforward electrical system.
That said, if you find it helpful for your own reasons, and don't mind the requirement to buy several different colors and quantities of wire, then by all means go ahead. I think the situation where specific wire colors would make the most sense is in a dedicated wiring harness, where other means of identification--such as troubleshooting a wire mid-harness--might be difficult.
For most normal identification purposes, I'd suggest that careful wire labeling at the wire terminus is a better and more effective overall practice than sticking to chapter and verse of the ABYC recommendations for wire color.
And don't worry: not having every wire installed using the specific color code suggested by ABYC is not going to be a problem at survey or insurance time, unless your surveyor has no common sense at all and determines to ensure that every letter of every ABYC standard is met. I've never known anyone to come even remotely close to calling a 2-color (red/yellow or red/black) wire system unacceptable for any practical purpose. Special ABYC colors are fancy-dancy, but aren't widely used. It's often tough to even source some of the colors in marine wire.
There's nothing wrong with using basic fuse panels instead of circuit breakers, particularly for such a straightforward system. But remember that either way, many of the things you're installing will require their own fuse in addition to whatever you have in the panel; the fuse or circuit breaker panel protects the wiring, while the inline fuse as directed by the equipment manufacturer protects the inner workings of that specific device. Depending on available space and your inclination, it might make sense to plan for a dedicated fuse block somewhere that you can use to organize all your device fuses in a common location.
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Forum Founder--No Longer Participating
When I rewired my boat, I bought a roll of 14 AWG Ancor 2 conductor wire. It was I believe red/black, and sheathed in white. To colour code it, I simply bought some Jiffy Markers in various colours. When I ran my run, I pulled the wire through my hand, with a Jiffy marker pressed against the white sheathing. I also labelled the wires at the terminus.
Some insurance companies are starting to require the VHF to be on the hot bus (not switched from the battery). You may want to check with your insurance company.
You have a circuit labeled "mast." Is that for a Steaming Light (forward 225 degrees) or is it for an all around (anchor) light? It is not clear if you have an outboard. If you do, you need a steaming light. It is also convenient to have an all around anchor light but that may be the purpose of the outlet.
Breaker panels are much easier to deal with and they don't seem to have as much of an issue with corrosion but they are more expensive.
Thanks for all the input so far, I appreciate it.
@Tim - Yea, I kinda went back and forth on the color code, but figured that as long as I was drawing it out I might as well do it "right" so I had it figured out if I went that direction; I'll probably just use duplex after all. Thanks for the confirm on the loads, 14 AWG is cheaper :-P Most of this wiring will all be in one cabinet, so an extra fuse block should be no problem. I forgot about the extra set of fuses.
@Dennis - Yea, mast is the anchor light. I wasn't thinking about a steaming light. Considering that I rarely, if ever, will be moving about at night, I think I can rig up a steaming light temporarily if I need to. I'm trying not to get too fancy here. The 12V Outlet is extra, mostly for charging cell phones, running handheld spotlights, invertors, that sort of thing.
Regarding the solar panel, I've not played with these before, do I have it wired correctly? This would be a small panel, most likely, unless I find a heck of a deal on a bigger one. If I need a charge regulator, it just goes in series with the hot lead, correct?
Oh, and the VHF thing...how are they gonna know? I can always change it to the always hot bar later if necessary.
For the really small solar chargers (trickle chargers) I think they are usually just wired up to the battery like you have it.
The larger panels have charge controllers with reverse current diodes to prevent the cells from discharging the battery at night. I researched it at one point for my 50 watt panel but I have forgotten the details now. I suspect the solar panel will come with explicit instructions for connecting it. Mine did.
A masthead anchor light is good- I plan on adding one - but I really like the ability to hang a lantern/electric light lower on the forestay (or even backstay). The light up high can blend in with the stars or is otherwise not immediately in the field of view. I like the light just off the deck (about head height actually) because it is easier for other boats coming into the anchorage to pick it out. Your 12v outlet could power this sort of light easily too. Definitely install the outlet. You will find all sorts of uses for it.
-Britton
-Britton
Work is overrated.
Most everything you read on the Internet is wrong.
Master fuse to the hot buss, I may connect other things to it over time, and the bilge pump is hooked to one of those nifty Rule panels with the on/off/test switch and fuse.
I was going to ask you about the double fuses. I think I would go with just the rule fuse for the bilge pump (as pointed out by Figment). I wouldn't want the boat to sink because of a blown fuse. Even if the feeder cable heats up a bit.
I'll think about the fuse thing. I left off the memory lead on the stereo intentionally, to save power. I won't have any power generation on the boat aside from the solar panel, and that's more of a keep-full type thing. To get enough panel-juice to really charge the battery would cost more than I paid for the boat! I'm not too concerned about saving presets long term. I'll hook up the lead to the switched buss, so while I'm using the boat I can save something, but I don't mind searching for the channel every once in a while otherwise.
Brian,
Our C-22 will be trailer-sailed only for the close future. I have a charger at home and will charge the system there. The solar panel is for keep-full charging while it sits on the trailer during trips and on the water. I don't have the panel yet, so actual performance is up in the air, still. Thanks to the recent arrival of my first child (Very Exciting!) and a car accident before that (exciting in a far different way...:-0 ), my funds are a bit skim, so I'm doing things as I can. This year I've got a significant chunk of time off work coming, a part of which I expect to be able to take 2-3 extended river cruises, and possibly some cruising in the Puget Sound, depending on how I feel about my own ability. During that time, I don't know what facilities will be available to charge with once my battery's depleted. I'm using battery-powered LED pucks to provide interior lighting, and my outboard is manual start, so even if I have no 12V available, I can still sail, motor, whatever. Bilge pump will be backed by a manual pump and galley water is a hand pump. I picked up some of the parts for the 12V system yesterday (most wiring, buss bars and battery meter), so I may be able to get started this weekend, we'll see. I still have to get my tow vehicle running (rebuilt Jeep motor, idles but not happy at RPM) so my weekend (sun-wed) will be Bizzzy!
Assuming that the fuses immediately in line after the battery are the bug-mutha ones sized as necessary to protect the wiring (not the devices), I suggest having only one, and splitting the line from a bus after it. They don't give them away.
Fig,
My thinking here was, rather than use one of the "Big Mutha" fuses (I like that, by the way :-), I could use 3 smaller (Little Mutha?) fuses, one on each leg. Upside would be easier troubleshooting if I'm getting blown fuses. If I have one fuse on everything, I have to follow each circuit. If I have a fuse on each leg, then the problem is already narrowed down some. Downside is more complication, more chances of false alarms due to a bad fuse.
Another issue I'm thinking about is whether I need to put a momentary switch in before the battery meter. I picked up a nice Weems and Plath charge meter at a consignment shop for a $20 the other day. Anyone know what kind of current draw these things have?
OK,
Here's the plan up to now. Amperage and fuse values are mostly estimated based on Don Casey's This Old Boat as well as online sources. Am I on the right track here?
What are you planning on running through that 12V outlet that led you to spec 10AWG wire for it? 14AWG will handle any load that the typical 12V outlet can handle, and I can't imagine that you'd run anything that required more than 14 could handle.
Also, you don't need that small separate negative buss downstream of the electronics; the negative leads can go directly to the common negative distribution buss. However, a separate buss might make sense if the electronics are located far away from the main buss, so that you can reduce the number of wires you run back to the main buss. These are the things a drawing can't adequately convey.
Remember that the fuses in your main distribution panel are intended to protect the wiring itself, and should be sized below the maximum wire current allowed, but safely above the actual anticipated draw. I'd suggest that you use larger fuses than you've shown for many of the circuits, since you run the risk of frequent fuse blowouts if, for example, you use 2.5A main fuses for a circuit that might draw 2.4A in regular use, such as the lighting circuit you've indicated.
For loads of the size you've indicated, I'd suggest 10A fuses for the main panel, which is more than adequately conservative to prevent any wiring damage should there be excess current. Again, it's nice to standardize things to the extent practicable. All of your anticipated loads are well under 10A, so there's no need to use a fuse larger than that, but going much smaller runs the risk of irritating blown fuses during normal use. (As an aside, most circuit breaker panels now come with all 15A breakers, which is a safe size for typical 12AWG or 14AWG wiring.) You might consider a 15A fuse for your electronics circuit, since all devices running at their highest amperage values might come close to risking a 10A circuit fuse.
Things like lighting circuits don't require inline fuses to protect the devices individually, and require only overcurrent protection that's spec'd high enough to allow for normal usage without running the risk of ever exceeding the wires' capacity.
As you've shown for your electronics and bilge pump, certain devices require a specific inline fuse designed to prevent damage to sensitive internal circuitry, the amperage rating of which is always specified in the device manual. Your stereo may also end up with one of these, depending on what your instructions say once you source the unit.
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Forum Founder--No Longer Participating
Marshall,
I'll see if I have time today for it. Final is basically what you see minus the small negative buss after the combination circuit (That was actually out already when Tim mentioned it) and with Tim's recommendations regarding fuses taken into account. The heavier wire to the 12V socket is a just in case thing, I plan to sell the boat some day and want to make sure that that circuit is pretty robust, since there's no way to know what might actually get plugged into it. For me, it'll be inverters and spotlights, mostly. There will be another fuse inline to the stereo to protect the device. That's pretty much it.
Well, crap. Yahoo closed my webpage and I forgot this schematic was stored there. I don't suppose anyone has a copy they downloaded? I forgot to print one to keep on the boat and dumped a cup of hot chocolate into the laptop this file once resided one.
Tony wrote:I'll think about the fuse thing. I left off the memory lead on the stereo intentionally, to save power. I won't have any power generation on the boat aside from the solar panel, and that's more of a keep-full type thing. To get enough panel-juice to really charge the battery would cost more than I paid for the boat! I'm not too concerned about saving presets long term. I'll hook up the lead to the switched buss, so while I'm using the boat I can save something, but I don't mind searching for the channel every once in a while otherwise.
I did the same.
Wonder if you could wire up a set of nicads at the receiver that would charge while underway and using stereo and discharge when breaker is off to keep presets?
