A/C wiring the C27 from scratch - Page 2 - SailNet Community

   Search Sailnet:

 forums  store  


Quick Menu
Forums           
Articles          
Galleries        
Boat Reviews  
Classifieds     
Search SailNet 
Boat Search (new)

Shop the
SailNet Store
Anchor Locker
Boatbuilding & Repair
Charts
Clothing
Electrical
Electronics
Engine
Hatches and Portlights
Interior And Galley
Maintenance
Marine Electronics
Navigation
Other Items
Plumbing and Pumps
Rigging
Safety
Sailing Hardware
Trailer & Watersports
Clearance Items

Advertise Here






Go Back   SailNet Community > General Interest Forums > Gear & Maintenance > Electrical Systems
 Not a Member? 
  #11  
Old 04-07-2010
sailingdog's Avatar
Telstar 28
 
Join Date: Mar 2006
Location: New England
Posts: 43,291
Thanks: 0
Thanked 8 Times in 8 Posts
Rep Power: 13
sailingdog is just really nice sailingdog is just really nice sailingdog is just really nice sailingdog is just really nice sailingdog is just really nice
I doubt your boat has the through-hulls bonded. If you look at the through-hulls, do they have a wire connected to them that goes to the other through-hulls? If not, then you don't have one.

One reason to have multiple circuits is simple... if you're working on your boat, you may want to use 110 VAC lighting and power tools, but may not want to have the DC side energized. If the 110 VAC charger is on the same circuit as the outlets, you can't do that.
__________________
Sailingdog

To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.

Telstar 28
New England

You know what the first rule of sailing is? ...Love. You can learn all the math in the 'verse, but you take
a boat to the sea you don't love, she'll shake you off just as sure as the turning of the worlds. Love keeps
her going when she oughta fall down, tells you she's hurting 'fore she keens. Makes her a home.

—Cpt. Mal Reynolds, Serenity (edited)

If you're new to the Sailnet Forums... please read this
To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
.

Still—DON'T READ THAT POST AGAIN.
Reply With Quote Share with Facebook
  #12  
Old 04-07-2010
smackdaddy's Avatar
Last Man Standing
 
Join Date: Aug 2008
Posts: 12,704
Thanks: 71
Thanked 61 Times in 55 Posts
Rep Power: 8
smackdaddy is a jewel in the rough smackdaddy is a jewel in the rough smackdaddy is a jewel in the rough
Quote:
Originally Posted by sailingdog View Post
I doubt your boat has the through-hulls bonded. If you look at the through-hulls, do they have a wire connected to them that goes to the other through-hulls? If not, then you don't have one.

One reason to have multiple circuits is simple... if you're working on your boat, you may want to use 110 VAC lighting and power tools, but may not want to have the DC side energized. If the 110 VAC charger is on the same circuit as the outlets, you can't do that.
Thanks for the feedback dude. The thru-hulls are not bonded. And we're in fresh water - so maybe that negates the problem as well.

As for the scenarios requiring the need for multiple circuits, I think that what we're using the boat for the single circuit will work as shown in the original diagram - for now. When I need to work on the boat as you lay out above and need more power options, I can just go back to running the extension cord to the slip outlet. I can live with those limitations. At this point, the simpler the better...and I'll save $150 bucks! That equals a bottle of good rum you know!
__________________

To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.


To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.

S/V Dawn Treader - 1989 Hunter Legend 40
Reply With Quote Share with Facebook
  #13  
Old 04-07-2010
sailingdog's Avatar
Telstar 28
 
Join Date: Mar 2006
Location: New England
Posts: 43,291
Thanks: 0
Thanked 8 Times in 8 Posts
Rep Power: 13
sailingdog is just really nice sailingdog is just really nice sailingdog is just really nice sailingdog is just really nice sailingdog is just really nice
Make sure you're using a good GFCI protected extension cord with a circuit breaker in it. The shore power post's 30 amp breaker won't protect the 15 amp extension cord from frying itself.
Quote:
Originally Posted by smackdaddy View Post
Thanks for the feedback dude. The thru-hulls are not bonded. And we're in fresh water - so maybe that negates the problem as well.

As for the scenarios requiring the need for multiple circuits, I think that what we're using the boat for the single circuit will work as shown in the original diagram - for now. When I need to work on the boat as you lay out above and need more power options, I can just go back to running the extension cord to the slip outlet. I can live with those limitations. At this point, the simpler the better...and I'll save $150 bucks! That equals a bottle of good rum you know!
__________________
Sailingdog

To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.

Telstar 28
New England

You know what the first rule of sailing is? ...Love. You can learn all the math in the 'verse, but you take
a boat to the sea you don't love, she'll shake you off just as sure as the turning of the worlds. Love keeps
her going when she oughta fall down, tells you she's hurting 'fore she keens. Makes her a home.

—Cpt. Mal Reynolds, Serenity (edited)

If you're new to the Sailnet Forums... please read this
To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
.

Still—DON'T READ THAT POST AGAIN.
Reply With Quote Share with Facebook
  #14  
Old 04-08-2010
Senior Member
 
Join Date: Jul 2008
Location: Oregon
Posts: 142
Thanks: 0
Thanked 0 Times in 0 Posts
Rep Power: 6
MtHopeBay is on a distinguished road
Quote:
Originally Posted by smackdaddy View Post
...and I'll save $150 bucks! That equals a bottle of good rum you know!
I like your thinking but I've never run into a $150 bottle of rum. The kind I like would get me 4 bottles for $150.

I'm putting in shore power this spring too. My boat's never had shore power so I had to rely on solar to keep my batteries up. My lighting is all 12V so I want shore power for 2 things: battery charger and space heater. I'm going with a main 30 amp breaker and two circuits/breakers of 15 amps each. Not sure of the exact brand yet because I'm shopping around.

I'm hoping for $35 left over for a bottle of Rogue Rum.
__________________
Catalina 27
Hispaniola
Reply With Quote Share with Facebook
  #15  
Old 04-15-2010
smackdaddy's Avatar
Last Man Standing
 
Join Date: Aug 2008
Posts: 12,704
Thanks: 71
Thanked 61 Times in 55 Posts
Rep Power: 8
smackdaddy is a jewel in the rough smackdaddy is a jewel in the rough smackdaddy is a jewel in the rough
Okay - so I'm making progress on this little project. First, our marina shore power is 20 amps. I was told this by a neighbor and looked at the breaker panel. All breakers are indeed 20 amps. So I got that goin' for me.

Now, being the glorious hack I am, I bought a locking 3-prong plug for the boat end and connected it to a standard heavy duty extension cord for the shore connection. I then dropped 12/3 wire into the boat from the shorepower plug down into the dinette seat where the batteries are stored. I then wired in a GFI plug to test....plugged it in to the shore power....and....I had indeed successfully built a much more complicated extension cord. I got the powa.

To reiterate my planned use: I want to add two GFI outlets, one in the dinette seat area with the batteries (for a charger) and one in the forward hanging locker (for a light, etc.). Very simple stuff. The boat is in a fresh-water lake and will only use my slip's 20 amp power.

Now for all the stupid questions as I try to finish this up. Bear in mind, I understand a little about electrical work, but am still missing very basic pieces of the AC/DC puzzle...so here goes...

1. I don't get the whole ground thing as it relates to my boat. If I had an inboard motor, I do get running a ground wire from the buss to the engine and calling it done. But at this point, my buss is not really grounded to anything. I only have DC house power (no starting) and everything has worked fine thus far. But, now that Dog has mentioned running the ground from the AC into the DC buss, it's got me wondering. Should I run a ground from the buss to something else? Though I don't know what it is, there is a 1/8" threaded stud in the floor of the engine compartment that is not being used for anything.

2. What drives the need for the AC circuit breaker in the boat? Keeping in mind the fact that I'm on a lake and will use the exact same setup all the time, and taking into consideration that my shore power outlet is already on a 20 amp breaker at the shore box, is it really necessary to add another 20 amp breaker in the boat? And if so, why? I guess in thinking about my single circuit needs, and having used an extension cord for two years for all AC needs, I'm trying to understand the need for more complexity in the system.

3. What are the pros/cons of running cabin lights off the batteries while they are being charged in the slip? Does this hurt anything? If not, is there a good reason to add an AC light? Dog also mentioned a scenario where you might want to have AC power without having the DC side energized. I guess I could just unplug the charger in this case right?

4. Is it cool to wire the charger into the buss to charge the bank? Or should it go directly to the battery?

5. What the hell are these 3-pin outlets? They seem to have been wired with 14/3 at some point. Are they AC outlets or com ports?







Nothing has blown up yet. But I'm pretty sure that MaineSail would weep if he saw my work.

(PS - How about that bitchin' new SN battery switch? Yeah baby!)
__________________

To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.


To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.

S/V Dawn Treader - 1989 Hunter Legend 40

Last edited by smackdaddy; 04-15-2010 at 01:32 PM.
Reply With Quote Share with Facebook
  #16  
Old 04-15-2010
Stu Jackson's Avatar
Senior Member
 
Join Date: Jul 2001
Posts: 716
Thanks: 0
Thanked 2 Times in 2 Posts
Rep Power: 13
Stu Jackson is on a distinguished road
You're doin' fine so far!

1. Written for a friend who had almost the same question. Catalina 34, inboard diesel.

AC DC Ground Connections on your boat
: Connecting the AC and DC neutrals is a completely separate subject from bonding the neutral and ground wiring, which I may have confused in the online topic discussion. AC DC ground connections on board is the subject of this: shorepower wiring whenever you are plugged in creates the risk of corrosion of any underwater metal fitting connected to the DC ground, primarily the propeller and the shaft and any bonded through hulls (not likely on your C34, they're Marelon unless someone or you swapped them out). Galvanic isolators (poor) and isolation transformers (heavy and expensive) are the "cures" for this condition. >>
Accordingly, even though I don't leave my boat plugged in very often, but have to sometimes, and because I don't trust my dockmates' ability to understand boat AC electricity any further than I can throw their boats (J) and they are all plugged in all the time, I have deliberately chosen to NOT connect the AC and DC grounds. Catalina didn't do it out of the factory. I know of few, if any, C34 skippers who have done this. I do not recommend you do so, without appropriate "protection" and even with a galvanic isolator
>>
While what Kent may have told you is "doable" I do not recommend that you connect your AC and DC grounds without at the very least a galvanic isolator, or better yet an isolation transformer. It is my understanding that the C34 Mark IIs, at least the later ones, came with galvanic isolators. From your hull # it appears you may very well have one. Even so, the superiority of the isolation transformer over the galvanic isolator might give you pause to connect the AC and DC on board grounds, especially if you have the boat plugged in all the time, as some folks do. Even with the galvanic isolator, you risk corrosion of your shaft and prop.

2. It protects the wires between and downstream: shore breaker wire to boat, you OWN on-the-boat breaker your wiring. Buy a book or look up more details online like West Marine Advisors, BoatUS...pretty well covered.

3. No problem with 12V DC running when charging. Rather than a plug, it's a switch. Your boat, your choice. Just one less thing to do: easier to flip a switch after solidly wiring it in. Less expensive, and certainly less "elegant" the other way.

4. What bus? Going directly works just fine, different end of the same wire.

5. Dunno, but that small a wire sounds like 12V, some connector. Look behind it and follow if there are any wires. Play detective.

__________________
Stu Jackson, C34, 1986, M25 engine, Rocna 10 (22#)

Last edited by Stu Jackson; 04-15-2010 at 08:30 PM.
Reply With Quote Share with Facebook
  #17  
Old 04-15-2010
smackdaddy's Avatar
Last Man Standing
 
Join Date: Aug 2008
Posts: 12,704
Thanks: 71
Thanked 61 Times in 55 Posts
Rep Power: 8
smackdaddy is a jewel in the rough smackdaddy is a jewel in the rough smackdaddy is a jewel in the rough
Cool. Thanks for taking the time to respond Stu.

So to make sure I understand - you say DON'T "ground" either the DC or AC? Simply run the AC ground wire into the "negative" side of the DC buss and call it a day?

And now that I'll be getting that breaker, let me make sure I have this part right as well...the line comes into the breaker from the plug. The ground wire comes out from that to the buss. Then the line for the outlets comes out of that breaker connection and runs to the first outlet (then onward). Right?
__________________

To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.


To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.

S/V Dawn Treader - 1989 Hunter Legend 40
Reply With Quote Share with Facebook
  #18  
Old 04-15-2010
mitiempo's Avatar
Senior Member
 
Join Date: Sep 2008
Location: Victoria B.C. Canada
Posts: 6,749
Thanks: 0
Thanked 49 Times in 40 Posts
Rep Power: 6
mitiempo will become famous soon enough
smack
I wouldn't connect the AC ground (green wire) to the DC bus as in your case it would not do any good anyway. In your case as far as I understand everything DC ends at your battery. If you had an inboard it would be different as there would be a path to earth (the water) in case of a fault.
Did you buy the double breaker you linked to? If so run the white and black wires to the breaker and continue the green to the outlets.

AC circuit breakers are there to protect you and yours. The dock breaker will do nothing for you if there is a fault on the boat.

Yes it makes sense to run 12 volt lights when the charger is plugged in as they are already there so no need to use 120 volt lights.

If you have a negative bus instead of running all the negatives to the battery yes the charger's negative out can also connect to this bus. The charger positive out goes to the battery positive.

Don't know what those outlets are but could have been AC as 14/3 is the standard gauge for 15 amp ac circuits.

Hope this helps.
__________________
Brian
Living aboard in Victoria Harbour
Reply With Quote Share with Facebook
  #19  
Old 04-15-2010
hellosailor's Avatar
Senior Member
 
Join Date: Apr 2006
Posts: 10,037
Thanks: 0
Thanked 50 Times in 49 Posts
Rep Power: 10
hellosailor has a spectacular aura about hellosailor has a spectacular aura about
Smack-
Two things. First, as I recall the ABYC and perhaps USCG both want to see a GFI, and only one GFI, installed as close to the shore power conection as possible. Maybe 18" maybe 4 feet...someone else will come up with the precise number, but the correct procedure is to install one GFI device as close to the shore power connector as you can while still making it accesible, i.e. through a locker or other access.
And having done that--you don't need any others. In some situations, GFIs will "fight" each other and cause false trips if they are on the same line, so having two is not necessarily better than having just one--located in the right place.

On a megayacht like the Smacktanic, one really could argue that just having the GFI and ONE main breaker for the two AC outlets, would be more than sufficient. I mean, if the breaker blows and you've only got two outlets, you can certainly figure out what to unplug, right?

Running one breaker per outlet certainly is better design, since each breaker can protect one wire run, but at a certain point you have to say "Do I have room for that pricey new panel, on thebulkhead and the budget? Or would one double-breaker all by itself really be enough to do this job?"

I'd vote for just the one and KISS.

The purpose of the breaker(s) on your boat is to protect your own wiring on your boat, whether you are at your home dock or elsewhere. Since 30A service is fairly normal at US docks, and 20A is below normal, I'd install a 30A main breaker on the boat. And make my wiring capable of taking MORE than 30A on each run, so that no matter where you plug in a 30A load, your wiring will be safe and your breaker is what will let go.

Yes, that also means if you plug in Too Much Stuff (George Carlin, RIP) you will blow the marina's breaker instead of yours. That's OK, their breaker protects their wiring, your breaker protects YOUR wiring.

And if you're loading things up on a hot summer night with low voltage (another common thing at docks) that way you won't be stuck with the lowball 20A breaker shutting you down, at some other marina.

Other little things: You'll probably be using "romex" i.e. all plastic cable. Just make sure that is secured every 18" or so and chafe protected where it runs against edges. And preferably run it somewhere that you won't accidentally put a screw through it while mounting anything else. You'll also see a variety of boxes and fittings at the hardware store, the guys there can set you up with all the little bits that make a good installation, including the little fittings and anti-chafe bits to protect the wire where it goes into the outlet boxes.

If the outlets have "speed" inserts on the rear, where you can just push in the wires instead of using the screw terminals? Don't use them. The speed inserts rely on a knife edge of metal contacting the wire, that's less contact area than the screw connections, it corrodes and overheats and fails faster. (Ah!). And after you connect up the wire to the outlets? Wrap around the outlet body with a couple of layers electrical tape, so that no one can accidentally touch a hot screw contact if they move the outlet, or it moves at a later date. Little things, an investment in preventing accidents and failures down the line.
Reply With Quote Share with Facebook
  #20  
Old 04-15-2010
mitiempo's Avatar
Senior Member
 
Join Date: Sep 2008
Location: Victoria B.C. Canada
Posts: 6,749
Thanks: 0
Thanked 49 Times in 40 Posts
Rep Power: 6
mitiempo will become famous soon enough
I wouldn't use romex - only stranded marine wire, preferably tinned. The breaker that smack linked to earlier is not designed for romex anyway.
__________________
Brian
Living aboard in Victoria Harbour
Reply With Quote Share with Facebook
Reply


Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools

 
Posting Rules
You may post new threads
You may post replies
You may post attachments
You may edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is On


Similar Threads
Thread Thread Starter Forum Replies Last Post
Catalina C27 Tall vs. Std. Rig Fin vs. Wing Keel mmazour Boat Reviews 14 06-03-2010 07:26 PM
Boat A/C Wiring there are some great resources available NewsReader Mass Bay Sailors 0 01-31-2007 08:15 AM
Need to run a/c mooring, no gen? acmecoyote Gear & Maintenance 4 11-19-2002 03:21 PM
Wiring Windlasses SailNet Gear and Maintenance Articles 0 09-19-2002 08:00 PM
Electrical Work Rules Don Casey Gear and Maintenance Articles 0 07-16-2000 08:00 PM


All times are GMT -4. The time now is 07:27 AM.

Add to My Yahoo!         
Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2014, vBulletin Solutions, Inc.
SEO by vBSEO 3.6.1
(c) Marine.com LLC 2000-2012