newbie electrical build questions

Hunky

Member
56
5
NW Alaska
I've wired a lot of houses when building them but never a boat. This is a 30' cat I picture the use of as coastal cruising - though don't want to limit it too much. So electrical demands are fairly light at this point. What I will have is all LED lighting, a lithium battery around 200-280 amp/hrs, vhf, ais, USB charge outlets, etc. I started this electrical install by looking at pictures of a previously similar boat so perhaps limited myself a bit on what I bought. There is no marine electrician in my very rural area and no way to get one here, at least in these covid times.

The images: first is the plan layout. Second is the 8 circuit panel for DC distribution, the third is looking aft at the location of the panel near companionway, and the last pic is looking forward. The last pic shows the central storage area where wires will penetrate the deck for up the mast and into the cuddy cabin (not shown), plus the battery will reside in the lower left storage space in that image. A starter battery for 2 - 18hp outboards may go behind that bulkhead in the looking-aft image. That aft looking image, where the panel is mounted, shows also where the starboard bilge pump control is on the cabinet, as well as a couple light switches. Radio in a cabinet to right side.

I'm not sure how to break out the circuits yet. The circuit panel I figured would be good for 1. Cabin lights (both port and stbd), 2. VHF and AIS, 3. Electronics like depth, wind, gps  4. Accessories: USB charge, propane solenoid 5. Auto pilot (eventually) 6. 7. 8.  I may add a water pressure pump, fans, small refrigerator/freezer like a powered cooler type. Radar may be down the road.

For the above deck cuddy I have a waterproof switch panel (no breakers) and for inside the center storage area a 12 position BlueSea fuse box (ST blades?). So my thought was to run from the positive battery bus (outside the battery switch) a wire to the center storage - to the fuse box - to the waterproof switches - the above deck lights: Nav lights, Anchor/TriColor (marinebeam style all on one), Steaming light, Spreader light, Compass light, and room for one more item. (I can also have room for some individual switches if I need to add to it). I have been looking at running the supply wire first to a switchable breaker, then to fuse box and up to switches. Reason is because the switches won't be locked up when I'm off the boat, and kids love switches - so I would like to cut power to them. I've seen the BlueSea switchable circuit breakers but the smallest is a 25 amp. Is that usable or should I use something else - or do something else entirely?

Also back to the circuit panel: I've been reading Nigel Calder's book that states it isn't good practice to combine many functions on one circuit, though he didn't outright disallow it. So I'm not real sure how to break out these circuits given the space I have. The AIS would have to be separate from the VHF as it doesn't include it. Combine electronics like depth, wind, gps? I could add a second panel perhaps in that cabinet with the VHF radio, though of course I am a cheap bastard and also don't want to usurp too much storage cabinets. There's perhaps room for a few more circuit breakers above the existing panel - a 3 or 4 place panel. The hole above it is for a battery monitor.

For charging I plan on a solar panel or two and carry a small generator until I can perhaps add more panels. Might need an inverter to charge batteries with generator (something like a Honda 2000 or 2200i).

Sorry for too much info but if anyone can work through it and offer suggestions, it would be greatly appreciated. I have lots of images if more are needed. 

30catintg.gif

circuitpanel.jpg

hull-aft.jpg

hull-forward.jpg

 

Hunky

Member
56
5
NW Alaska
I can't help with your question, but it looks like a nicely built boat.

Maybe you would get more traction on Fix-it anarchy.
Thank you! And thanks for the suggestion - I think I'm a bit too all-over-the-map and can maybe distill it a bit if I rephrase.

 
I've only done full wiring jobs on three boats in my life, so I'm no expert.

But I would recommend you have a larger panel with more breakers, as you grow into the boat you are likely to want them. I would 100% oversize the wire from the main panel to the battery. It's hard to follow the description of what you are doing to kiddie-proof this?  Maybe a diagram would help.  20 amp breakers are way to large. You want to use tiny wire to save weight/bulk and ease the install for the LED lights (like 18 GA or less) the ampacity becomes an issue, you should be able to use  down to 5 amp breakers in any panel you use. I would not combine all the instruments onto one breaker. Try to separate the VHF and GPS and AIS  and certainly never use a common wire to supply them from a buss or by splicing/junction box. Run a spare 16GA duplex marine wire to the forward area for future stuff. Always use tin coated class-k  marine wire and get familiar with shrink and seal connectors... I missed any mention of bilge pumps, fans, heater, and other common items?  You could include a circuit/device table?

 

Hunky

Member
56
5
NW Alaska
But I would recommend you have a larger panel with more breakers,....
Thanks much for that 2flit! I'll try to answer a few concerns. As a newb, I can't argue with the suggestion for a larger panel. The one I have now has 15 amp breakers - 6 of 8 spaces (2 yet to be purchased. I could swap them out for smaller breakers. Only concern for larger panel is space and cost.. which I suppose I can bite the bullet and figure out. Probably need to add a second panel somewhere. Right now my device list would be (not necessarily circuit list)

  1. cabin lights port and starboard (I've got LED strip lights and hope to have a couple task lights here or there)
  2. VHF (has GPS but figure wise to get stand alone GPS as well)
  3. AIS (maybe just receiver rather than transponder which would be on a wish list maybe)
  4. USB/12 volt plugs
  5. Depth gauge - wind gauge  (at this point I have no underwater thru-hulls)
  6. Propane solenoid
  7. Fans (ventilation) to be added later
  8. Possible water pump.. now I have foot pumps but it might be nice - something to double as deck wash?
  9. Possible refrig/freezer like the cooler types, not built in. Will just use regular cooler for now.
  10. I'm in fog prone area (latitude 64.5) so radar would be on wish list but not able to afford.
  11. Nice to have water tank and gas tank meters but will live without for now
  12. Then the Nav lights/deck. I have Nav bow and stern lights, but figure will possibly add the tricolor/anchor light from marinebeam, also will need the steaming light and a spreader light. All LED.
  13. No budget for chart plotters so hope to use for now a pad or laptop. Not yet sure about all that. See if I can work out a display for depth/wind.
  14. No budget for windlass. We'll see how my old man back works out with that.. maybe look for a manual one and let next owner install electric.

 I've so far wired in bow lights and stern - they all have 18 ga. duplex wire. I am using quality tinned wire for all wiring as well as quality shrink tube and connectors such as FTZ brand. I've roughed in 4 ga. wire to the panel, but that is based on smaller size and based mainly on LED lights, radio, gps, 12 volt plugs, a water pump, AIS, depth and wind gauges. That wire size will be sufficient if I break out more circuits to another panel elsewhere.

I have a bilge pump in each hull and figured I would not have them on circuit breakers but wired to positive bus (perhaps unswitched bus) and fused. Still researching charging - not sure I'll need an inverter for that but could be handy for other uses as well. Obviously need some kind of charge controllers for generator, solar. Working on a schematic diagram but not there yet until I get a better handle on this. I'll start looking at other panels and location. Could solve the questions.

As for kiddie proofing, that was just to cut power to topside switches. I think I can handle that with just an on/off switch below. I'll throw a picture or two in of the cuddy area showing the switches intended for the nav/running lights, with room for a depth/wind display.

PXL_20201102_211256577_v1.jpg

 
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bushsailor

Anarchist
691
188
QLD Australia
Only tip I can give is keep it simple. Less wiring and crap the better.

And label all wiring well. In 2 years if you have a problem you will not remember which wires do what.

 

Hunky

Member
56
5
NW Alaska
This

I'm actually a fan of cZone.....go figure
Ok, now I'm going to have to research cZone. Don't know anything about it - do you think it would fit my case? I was a network administrator so I can wire networks (based on cat5 anyway), but I'm new to the boat world.  Thanks! I guess....    :unsure:

 

SCARECROW

Super Anarchist
5,998
684
Melbourne, Aus
czone is our go to for all but the simplest of boats these days. It'll feel like an added expense at the start but will repay you over the life of the boat and even during installation time.

 

Boogie with Stu

New member
19
12
USA
Ok, now I'm going to have to research cZone. Don't know anything about it - do you think it would fit my case? I was a network administrator so I can wire networks (based on cat5 anyway), but I'm new to the boat world.  Thanks! I guess....    :unsure:
If you're done IP networking, think of czone as a switched network.

 

wjquigs

Member
74
8
Only tip I can give is keep it simple. Less wiring and crap the better.

And label all wiring well. In 2 years if you have a problem you will not remember which wires do what.
I agree. My trimaran has, I think, 10 fuses/switches on the panel and I'm probably using 4 or 5 of them. Obviously you need separate switches for nav lights, anchor light, etc. but unless a single circuit is going to have a high load (fridge, windlass), no reason not to combine circuits where it makes sense.

I have no wires in my mast. Steaming light is portable LED, anchor light plugs into CLA. VHF antenna is mounted above the cockpit. Pulling the wires out of the mast is one of the best things I did to the boat. Boat wiring specs are still based on incandescent bulbs and 100-watt radios. Do the math and wire appropriately, otherwise you're just adding unnecessary weight. But make sure you can pull and replace any wire if you need to. Keep it simple, launch the boat, and add whatever you think you can't do without later. You'll be surprised how fun and safe it is to sail your boat without a bunch of stuff you thought you needed.

I use Victron charge controllers, LiFePo batteries, and 230 watts of solar. No need for a generator.

If you're new to multihulls, you will find that you need much lighter anchors, so you don't need a windlass. My primary anchor on my 32-foot trimaran is an 11-pound Fortress. Worst case, you run the rode to a cockpit winch.

Looks like a great boat. I love Hughes designs. You're going to be very happy on the water.

 

Hunky

Member
56
5
NW Alaska
I have no wires in my mast. Steaming light is portable LED, anchor light plugs into CLA. 

I use Victron charge controllers, LiFePo batteries, and 230 watts of solar. No need for a generator.
Thanks for the great positive reply. I'm wondering what a CLA is that you plug your anchor light into.  Also, curious if you have a lead acid battery for start? Outboard? I'm curious about that - was thinking of going LiFePo for house, and if I go a smallish LA battery for start (2 - 18hp 2 stroke outboards the put out max 6.6 amps), I'm trying to figure out if I can use the outboards for any charging on lithiums.. maybe with a DC-DC charger or if I just don't use the outboards on the lithiums.

Jim

 




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