Designing Electrical System?

[FredV]

I'm getting ready to replace all of the 30-year old wiring in my 37C and would like some advice. I've mapped out all of the existing and planned 12v DC items in the boat and initially split everything up into separate circuits based on both location and to keep the total load below 15 amps/circuit. However, I'm wondering if it doesn't make more sense to separate the circuits into meaningful categories, like 1. Cabin Lights, 2. Nav Lights, 3. Nav Instruments, 4. Pumps, etc.

Anyone have any suggestions?

Thanks!

 

[Stu Jackson]

Sure, what was the first idea? Location? That'd drive you nuts eventually. That's why categories are so much better. Check a panel manufacturer website, like www.bluesea.com, or the WM catalog or online and look at the labels that are provided for DC panels. That should give you a clue. Pretty much the only splits I've seen for locations have been: port & starboard A.C. outlets and P&S or berth-oriented lighting. For your size boat, maybe not required. Sounds like a great project. Good luck.

 

[rardiH36]

Hello Fred:

I'm not an electrician, so won't be giving advice. Just will be reading responses to learn. But can you explain your post a bit differently -- as I can't really visualize your question?

Is there a reason you are not using the original panel's labels and switch/breaker assignments as a starting point for the new design? Is your query about say one 15 amp switch/breaker that is the "fuse" for say several low amp non-breaker sub-circuits with standard (non breaker) switches further along the circuit that will control stuff like cabin lights, running lights, VHF, etc? If so, if you have a short fault say up the mast that trips the breaker, then all the other functions on the "circuit" stop as well. (Well so much for my opening caveat that I won't be adding any advice!)

 

[Ed Schenck]

I'm with Rardi. What is wrong with the original panel layout? You can't really see it in the picture but you have the separate AC section to the right and then two DC columns of switches. The far left column has all the lights and the bilge pump. The center column is for instruments, autohelm, VHF, and assorted. With room for more.

 

[FredV]

Thanks, just what I was looking for. Although I do have the original panel, it's almost completely illegible - either the original labels are too faded or they were written and/or taped over (and the tape, of course, is that permanent stuff that can only be scraped off with a razor which also scrapes off whatever original label was under it!). Could I impose on one of you to send me the list of labels that's printed on your panel - there's no rush, whenever you're sitting on your boat and have 5 minutes to spare - I'd really appreciate it!

The reason I'm putting so much (maybe too much) thought into this is because I would really like to get it done right. I'm trying to consider all the angles, including location (just port vs starboard runs), total loads, and as pointed out by Rardi, backup and safety.

Thanks for your ideas!

 

[redhead78]

Sounds like u need a brother p-touch label maker.....Red

 

[rardiH36]

Hi Fred:

I'll be at my boat tomorrow and take some photos that should be crisp enough to see the original labeling. I have covered over a few of them to mark new equipment, but I would say the the labels and the real switches/circuits are still 85% as OEM.

Looking at Ed's photo, I believe that the 80-82 36 and the Cherubini 37 panels were the same, so you might get some interest out of this thread:

http://forums.hunter.sailboatowners.com/showthread.php?p=893709&highlight=panel

Regarding the taping over the original engraved lettering that you mention. The material of the panel is a sort of Formica. Pretty darn impervious to acetone and lacquer thinner. You might try to first carefully lift the edges of the offending tape with the edge of a box cutter blade or Exacto type knife and then gently brush lacquer thinner in the gap. This will likely soften the now hard adhesive so you can peel back some more tape away from the surface. Might take a while, but with luck you could get all the old label tape free from the panel without any real damage. Then continue to wipe clean with the lacquer thinner. If the white paint in the original engraved letter grooves comes off ... well a very fine brush and some white paint to fill in. Or get a "white-out" correction pen at a stationary store. You should be able to lay in some new white very cleanly.

Reverting with the pic's

Personally, I like the original panel look. Very retro.

To digress but along the same lines of old but maybe worth preserving; at a nautical swap meet a few months ago I bought an item from a booth sponsored by a youth sailing club. She also had an old vintage switch board by "Catalina Yachts" which she had noticed I had hesitated over. Being late in the day and not many buyers around anymore, she offered it to me at no charge. (However, because the proceeds were for the club, I did give some monetary consideration to the exchange.) Here's a pic of the panel. I have no real plans for the it, but in the event that I want a few new circuits in my electrical system, I might pull it out. Small enough and similar enough for an OK look right next to my existing Hunter panel. This Catalina part must have been from before the days when combination breaker/switches became economical. Instead, the set up is normal switches on the left and the corresponding fuse holder to the right!

rardi

 

[Ed Schenck]

I would never discourage a rewiring of our boats, just changing the layout. Behind that panel it is a rats nest. I would love to start over but most of the wiring is in places you could never get into. And that rats next is all so tight. Ideally a large panel in the back of that space with nicely labeled terminal strips would contain the original wiring. Then nice jumpers to the breakers with lots of length so you can get the panel out where you can work on it. Because you will always be fixing and adding. At my age I'd be dead before I could finish a project like that.

 

[guidera48]

Hunter 37c electrical panel

Visit my page on electrics. Web site still under construction but you may find some ideas. These pictures will be updated soon with the completion of the solar and wind panels.

Panel has a piano hinge on left side and swings open.

http://hunter37.homestead.com/Electrics.html

hope this will inspire you

Jose

 

[sail_4_me]

electric panel refit

Several people have done this to their 37c, this site has a lot of good information.

I've mostly completed my project. I went with :

-Blue Seas 8408 panel - 6 AC 15 DC switches
-Blue Seas 5511e 350 amp battery switch ( 2 simultaneous circuits, one for engine, one for house panel.
-Xantrex Linklite batter monitor
-Wema tank monitors ( drop-in replacement for my 1983 tanks + monitor )
-Xantrex Freedom 1800W inverter ( will take a spike to 3500W )
-teak plywood and a Dremel tool to shape it
-4 290 series flooded deep cycle batteries, 400 Ah total
-1 cranking battery
-Xantrex echo charger
-Balmar 60 series 100amp alternator, charges house bank, connected echo charger charges the engine battery
-Balmar ARS-5 regulator
-200 amp fuse on pos+ for inverter ( 2400 watts protection )
-100 amp fuse on pos+ from alternator to batteries to protect the alt )
-negative bus bar, from batteries, grounded to engine. All neg-loads on 1 side, ground on the other, and shunt connected to Blue seas panel
-New wire for all the charging gear and batteries
-voltage and amp sensors connected to blue Seas Panel from batteries and shunts
-lots of expensive tinned wire, shrink tubing, ring terminals, lock washers, a label maker....

Nigel Calder's BoatOwners Mechanical And Electrical Manual. This is the book you want, to study lightning protection, wire sizing etc.

It's been a real adventure, and I've learned a ton of stuff. Dont forget to label every wire you touch. Note also that my choices of gear, and design of the electrical system were my own, based on my own requirements, and may not work for you. Take your time, draw it out, answer all your concerns about grounding, circuit design, loads etc, and don't skimp on wire size, or safety components like pos+ battery wire covers. DC amperage is dangerous if you ground yourself.

The one thing I want to add next year, is an isolator on the shore-side power, to reduce the burn rate on my magnesium anode, which I replace every season. ( note - if your in fresh water, you should have magnesium or aluminum. Zinc is useless ).

This spring I cut the nav-desk top in two, about 6 inches from the right-side. On that 6-inch piece I mounted a 110AC GFCI outlet for the PC and TV. Varnished and shiny, it looks really nice. ( I also made a small secret drawer underneath. Shh its a secret... )

This summer when I'm in the North Channel for 3 weeks, and I need to charge the batteries, I'll start up the engine, rev to about 1,200 RPM, watch the DC meter show a 60+ Amp charge, See the Xantrex Linklite show the batteries are filling up. Then my wife and I will take a shower, and let the amps flow. Its going to be a great vacation!

 

[Maine Sail]

I've mostly completed my project. I went with :

-Blue Seas 8408 panel - 6 AC 15 DC switches

The 8408 is a tremendous AC/DC panel value for a 30-40 footer. That panel however can be set up for 18DC and 6 AC. You don't have to set it up for all 18 circuits on the DC side but you can if you want or need to. We have the same panel on our CS 36T and use all 18 on the DC side.

-100 amp fuse on pos+ from alternator to batteries to protect the alt )

I see this posted quite a bit and hope to clear up the confusion. Anytime you lead an alternator directly to a house bank, the battery bank, is a "source" of power and thus the wire for the alt needs to have over current protection within 7" of the battery to protect the wire, not the alternator. Unless your alt wire is the same size as the battery conductors then you need to size that fuse at under the wires max ampacity.

Alternators by their very nature are considered "self limiting" and as such they don't require over current protection at the alt end. They do require it to protect the wire within 7" of the battery + distribution post or bus bar.

If the alt feed wire is sized correctly then the alt has no possible way of exceeding the max ampacity of the wire, because it is self limiting, but the battery bank it is connected to does have the capability to exceed the wires ampacity.....



FredV,

For panel circuits you ideally need to figure what YOU will have on your own boat. Any Blue Sea panel can have any label you want and be set up/labeled 100's of ways.

To give you an idea here's what we run on a 36' boat:

Cabin Lights
Sailing Instruments
GPS
Radar
Nav Station Electronics
Refrigeration
Water Pressure
Macerator Pump
Cabin Heat
LPG Solenoid
Running Lights
Steaming Light
Anchor Light Main Mast
Anchor Light Radar Pole
Foredeck Light
Shower Sump
Ice Box Sump
TV

 

[sail_4_me]

Here's my panel setup for the 8408. I thought a lot about organization of the switches, so they are in logical groupings ( for me ) and priority top-bottom.

When I leave the boat, only the top-middle 3 switches are on ( DC main, bilge and fridge ).

When I arrive at the boat, I turn on all the middle DC, and all the right AC switches.

When I sail, I turn on the left-side DC switches on top, and those on bottom if its dark out. ( and I turn off the AC water heater )


Left side DC:
VHF
Sailing Instruments
GPS
Autopilot
running lights ( bow, stbd red/green)
Steaming light (at inner forestay, red/green )
anchor light (top mast, white)
speader lights ( at inner forestay, white )

Middle DC:
DC Main ( red switch )
Bilge Pump ( automatic )
Refridgerator
main cabin lights
water pressure ( includes shower sump )
toilet ( electric )
stereo
Nav Station guages ( Wema tank monitor )
Nav station lights ( Wema and blue seas panel lights )
spare
bilge pump 2 ( momentary + on switch, for 2nd bilge pump )

right AC:
AC main 30A
Reverse Polarity
computer ( AC outlet at desk, for TV and PC )
Cabin Outlets ( salon, bathroom and v berth )
Galley Outlets ( galley and rear berth )
water heater
spare
spare

 

[rardiH36]

Hi Fred:

..... I'll be at my boat tomorrow and take some photos that should be crisp enough to see the original labeling.

rardi

Here are the pictures of my panel. Sorry, but on the right vertical column of the DC section, I did re-label some of the breaker/switch functions and I added a few more to the empty holes in the panel face.

The Blue Sea panel as per Mainesail, sail_4-me and guidera48 certainly looks wow and I'm sure performs great. Brings the electrical system right up to 2012.

For my boat and modest electrical equipment items, everything I need still fits on the original Hunter panel. Behind it, I've made the rat's nest look much better and have cut back the ends of the OEM wire for crimping on new terminals wherever I found that clean copper remained. I made clean again -- to shiny copper/brass -- all electrical connection points on the back side of the panel, at the breaker switches, at the receiving end of the circuits. I think that because mine has always been a west coast boat with low humidity and mild winters, the original wires for the most part still looked good. A few runs I did rewire. New charger added. Solar also to maintain and slow charge. Fuses right at both battery's plus terminal now. Inspected the routing of all the high current wires to verify wire jackets/coatings are still in good shape and nothing is rubbing on anything sharp and metal. Brand new wiring up the mast. GFCI's now installed on each of the two AC circuits.

I realize that my boat's electrics can't be up to the latest standards without pretty much doing a complete tear-out and then all new. But I figure where I am now is probably equal to when the boat was new and for some sections an improvement.

 

[heritage]

Do you really have 4 bilge pumps?

 

[rardiH36]

Do you really have 4 bilge pumps?

Not actually. The total is three.

A moment of impreciseness when I labeled the board. The "micro pump" and "small bilge" are one in the same. The little pump is located in the lowest part of the bilge farthest aft. It will suck down to about 1/2" H20 leaving no water in the forward 95% of the bilge well. I have fitted it's discharge hose just at the pump with a small in-line ball valve. I open it and flip the panel switch on. When the pump starts sucking air, I close the valve to prevent the water in the hose from filling back into the bilge when the pump is off. Then I turn off the switch. When my boat isn't motoring, the amount of water entering through the packing gland is negligible. Actually during the summer, its slower than the evaporation rate. So the little pump assists with an almost totally dry bilge.

The bilge switch on the left-most column is OEM and it's matching fuse for the always ready mode is the round one at the panel's bottom.

The forward bilge pump does not have a switch, only a fuse. In the forward section, there is never any water, so it's intended only to operate when the boat is sinking. I won't be at the boat probably. So the battery will deplete (I don't connect to shore power) and the boat will sink anyway.

 

[FredV]

Rardi - thanks for the pix. Maybe I can re-use the panel and just make new labels (painting the existing engraved labels requires fine motor skills that abandoned me years ago!).

All - Great ideas, wonderful input - it's why I love this forum!