H25 Electrical

[ChiTownSail]

I am about to revamp the electrical system in my H25. As far as a basic setup for battery management, something that will run a stereo, and the basics on the H25 what have people been running? I am not in need of AC power really, but I am all ears.
Thanks

 

[DianaOfBurlington]

H25 house wiring

This system can and should be pretty uncomplicated-- not like mine having fourteen DC circuits plus AC shore power!

The original H25 system is pretty rudimentary and as soon as you add a stereo or a deck light you're overloading the original breakers, in number if not in amperage. You may consider a new 6-gang panel (or two, which is what I got). Mine came from Boater's World and were $32.00 each. They're not available any more but there are others; and they are simple and straightforward. Most come with the .25" slide-on quick connectors on the back. Use a heat gun and heat-shrink tinned-copper ('marine') connectors and you can make good, reliable connections really easily.

In the '70s these boats were wired with 16- and sometimes even 18-gauge primary wire. I have done calculations and found that, while considered nominal for primary wire, 14-gauge is more than large enough to handle loads for lights and so on for most boats. None of my 14-gauge in-mast runs are too long to lose any appreciable voltage. Some people prefer using duplex wire (red and yellow together in a white sheathing) but funnily enough West Marine doesn't seem to carry this in many stores. I used separate strands of yellow and red, zip-tied together, because it's smaller in diameter. If you are starting from scratch you should at least emulate ABYC codes and use red for hot and yellow for grounds on DC systems (black is used as hot for AC systems; so the ABYC insisted on something different to avoid confusion away from the connections or panels).

ABYC publish color codes for certain runs of wire so that in the future some electrician can ID what's going where. This code is published in the West Marine catalogue. As much as possible I have tried to use it. Especially when going to far corners of the boat in bundles, having other than all red-yellow pairs can help you keep your sanity. This matters a lot when you are reeving new cable runs up the mast.

I acquired some tinned-copper marine-grade 18-2 speaker wire on a West Marine closeout and used it not only for the stereo but going up the mast to the anemometer, which according to Sean at SR Mariner is perfectly adequate.

Needless to say, cut everything way too long and give yourself some safety margin before attaching connectors. But combatting excess wire is another kind of nightmare; so trim it to a sensible length once you've finished running it through the boat and know you've got enough to connect.

Label all the ends, both ends, of every circuit even if you think it's nonsensically redundant. Believe me, the time will come when you'll be glad you did. I used a letter code and marked the inside of the panels according to a schematic in the boat's bible (you don't have a boat bible book? --for shame! :naughty.

The difference in my system, which sounds overly complex, is that I don't like lumping too many things together on one circuit. You'll need the basics-- anchor, steaming, running and cabin lights. All these need separate breakers. You can put the 12VDC outlets with the cabin lights-- just be sure to size the fuses correctly-- but keep anything with a high draw or high heat (like a 12VDC searchlight) separate. I put the stereo and VHF together on one breaker because they share the same antenna and aren't likely to be both cranked on to the max at the same time. I also have red LED footlights on a separate circuit, the instruments and their lights on separate circuits, and a foredeck downlight.

I made a whole new panel over the quarter berth and it includes the fuel gauge and the battery voltmeter. These are activated by momentary switches (if you need to read one, you press a switch). I also mounted the Rule bilge-pump switch using its own panel, with fuse, to save a breaker there. This is the only circuit which is not wired to the master shut-off switch; so the simple 'away' mode is to just turn off the master switch and the bilge pump stays live.

For cabin lights I have the red and white 'night' and 'day' circuits wired to a rotary DPDT on/on switch, wired to one common breaker. At night it gets switched over so that anyone switching on a cabin light will get only the red bulbs; at day the reverse. This saves a breaker on the panel since the reds and whites are never able to be on at once. Maybe no-one else needs this but me; but I am an airhead and very likely to destroy my otherwise excellent night vision by switching on the wrong light at night.

Never wire any circuits directly to the battery. I know that some people buy those cheesy fused circuit blocks that mount right on the terminals and then cavalierly use Y-adapters to increase their capacity. For any 'cruising boat' these can get bogged down in a nest of wiring pretty quickly. Blue Sea make an excellent series of right-on-the-battery fuses to meet the ABYC (and many insurance companies') requirement that there be an overload fuse within 6-7" of the terminal. The Blue Sea ones are artfully compact and effective; and best of all require no further wiring, terminals, or added height to the battery.

All my yellow ground wires go to a Blue Sea buss bar that is connected to the ship's earth (here, the negative battery terminals). I was advised against grounding the ship (12VDC) circuits to a ground plate underwater. This is unnecessary and leaves you vulnerable to stray underwater current in the marina. The same goes for a simple shore-only AC system-- let the ground be your green wire led to the outlets on the dock. The GFCI and ground-fault warning lights on the AC panel will alert you to faults; just mind that you heed them.

If you have two house batteries, I recommend wiring them together as one bank and never separating them. There is no point to charging two similar batteries separately-- it will wear down the batteries and means only complication. I have two Group-24s of about 150 a/h total and this will run everything for 4-6 hours before I worry about dipping below 40%. And when do I ever run everything at full load?

The biggest drawback with my system is that the two batteries, though one bank, are separated by about 5-6 feet of primary cable, as they are under the ends of the main-cabin settees. This is for weight (and because it's where they fit). Hence the separate momentary switches for the voltmeter-- to check that the distant one is being charged as well as the nearer one. I checked and there is very minimal voltage loss over the size-4 cable.

I also have an engine-start battery separate from the house bank and this is connected to only the motor. Each of these banks has a Blue Sea 6006 on-off switch. I don't believe in 'both' on a battery switch-- I see no reason to combine dissimilar banks, ever. In an emergency you can always use jumper cables to access one enough to start the (outboard) motor. The engine-start switch is located over the galley so that with the companionway locked and the seat locker (where the fuel shut-off is) locked, the engine can't be started from outside.

I didn't buy it yet but I read bad online reviews of the ProSport 12 smart charger (the one we use for Cherubini Classic runabouts). I have never actually heard of real-world problems but may be inclined towards the Guest 10 instead, which has no bad reviews at anywhere I checked. I'd be interested in experience-based opinion on this.

A very good source for quality marine-grade electrical stuff is GenuineDealz on eBay. He has rolls in 25 and 100 ft of all the major stuff, is a Blue Sea distributor, and has plenty of decent inexpensive stuff like switches, breakers, fuses and so on. And he does not charge for shipping! --so buy all your battery cable from him!

Hope I did not drown you with this info. I'll be happy to hear your detailed questions-- and there are plenty of other people here who will provide help as well.

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[ChiTownSail]

Great info., thanks a lot for the response. I'll make an update once the project has started...

 

[KennyH]

Keep it simple.

I have installed a 2 battery switch in the locker with the 2 golf cart batteries in series. I thought I might install a second set of batteries but they have not been needed. I have a solar panel to charge and a motor that charges. I run a 1000 watt inverter for boom box and drills and cell phone charging etc. I run one fan when its hot. I run a autohelm 1000 when cruizing. I have replaced most of the lights with floresent lights. Running lights are still regular 12 volt bulbs. I run a small GPS a VHF and a floresent anchor light. I think the golf cart 6 volt batteries from Sam's Club are the secret along with the solor panel.

 

[DianaOfBurlington]

Is anyone able to tell me, with authority, the true benefits of using 6-volt batteries wired in series over 12-volt batteries wired in parallel, specifically for use in small boats?

 

[Maine Sail]

Is anyone able to tell me, with authority, the true benefits of using 6-volt batteries wired in series over 12-volt batteries wired in parallel, specifically for use in small boats?

Two words - cycle life

For example Trojan rates their 6V T105 batteries at double that of their deep cycle 12V SCS series batteries. 6V batteries at DOUBLE the factory rated cycles of the same brands 12V batteries..This is because 6V batteries have thicker more robust plates than do 12V batteries.

Also they produce more Ah's per sq in of floor space. If you have the height they should easily last longer and give more Ah's for the foot print..

They also usually cost less per Ah. Of course the real quantifiable savings come from the longer life they give when compared to a group 24, 27 or 31 12V battery.

 

[Ed Schenck]

Maine Sail convinced me JC. Two winters ago, after ten years of very expensive Gels and AGMs, I converted. I cleared out a locker with five batteries totaling about 380 amp-hour for the four house batteries at a cost of $1000. to replace. In their place I have two 6V batteries in the bilge with 225 amp-hours that cost $80. each. These are DuraCells from Sam's Club.

 

[KennyH]

We should also mention the lighter weight of a 6 volt battery is a plus when you get older and have to lift them and carry them down the dock when they get replaced.

 

[DianaOfBurlington]

Thanks for all the advice, Maine Sail and Ed & Kenny. I recently refurbed a 1959 Swiftsure in which the owner had mounted two 6-volt size-24 batteries. The two batteries were mounted in cockpit-seat lockers, one to either side, and wired across under the cockpit using way too much wire. When 6-volts are wired together as one bank the goal is to keep the connecting wires as short as possible. I relocated them side-by-side to one side and 'balanced' the boat by relocating the hot-water heater to the other side (well, close enough). The owner was very satisfied with this.

Unfortunately on Diana I have a similar problem-- two battery boxes, one to either side, mainly for weight distribution and because I can't fit them side-by-side anywhere unless I put them under the cockpit; and this is a small boat and already susceptible to getting out of trim. I did, however, upsize the crossover wires.

I suppose I can yet use two 6-volt cells anyway. I will take this under consideration in getting new batteries for this boat before it goes into the water (soon).

Thanks again for the two pence!