The 12-Volt lights in my 78 Argosy 6-Metre Minuet were sometimes working and sometimes not. Process of elimination: Replaced some blown fuses. Got new battery. Lights worked intermittently after that, then stopped altogether. Got new converter/charger, wired it in. Nothing for about 24 hours; now back to sometimes yes sometimes no. I was able to identify which fuse worked which light, mostly. LR light & stove fan on one; bathroom light & vent fan on another. Don't know yet about Kitchen light; it came on briefly but won't come on again. Questions: Is the problem in the fuse panel? Can I clean it up? Do I need another one? Where would I get a replacement? It has glass tube fuses.
Thanks for reading this far. The rest is just about "The Dragon," 1978 Argosy 6-Metre Minuet. FYI: I've had The Dragon for about ten years and used it mainly for guest quarters. But when I tried in vain to get to the electrical works under the dinette unit, I said, "That's enough!" and proceeded to remove that built-in and the sofa/bed, the closet, the water heater, the furnace, the refrigerator, the water tank, and other space occupiers (most of which had quit working anyway). The bathroom is intact, as is the sink/counter/stove section and the overhead bins. I'm covering the floor with a layer of masonite with a nice finish. Across the front will go the Studio Sofa Sleeper like they have at World Market for $400, but I got one on craigslist for $75. Where the sofa/bed was on the side will be for eating, with table built over wheel well now exposed. It's now nicely open and more spacious and on its way to being a lovely guest house.
I also removed the AC from on top (quite a job singlehandedly) and replaced it with a skylight made from a sandwich of two pieces of plexiglas, with sealant on the top side. I plan to put a small AC in the 12x16 opening where the water heater was.
I reconnected the water lines so that the supply line goes only to the bathroom and the kitchen (now that water tank is no longer needed). Severed hot water line; not needed.
All of this was decided based on the amenities (none) in my '65 Shasta 13', which I actually use to go camping. With shore power available, comfort can be had without so many appliances. Still have LP for cookstove in both.
I agree that the fuse panel should absolutely be replaced. As they age, the metal in the old original fuse panel can rise in resistance and not conduct properly. I had the exact same problem with the cabin lights as you, and replacing the Univolt and fuse panel cured it.
The newer fuses are easier to locate too, should you ever need them. I was told at West Marine that the glass 'barrel' fuses are on their way out, don't know if this is true or just his opinion.
I *think* ATC means "Automotive Type, Closed" where "closed" means the fusible link is enclosed in the plastic housing. I've heard of "ATO" fuses where the fusible link is not covered by the plastic housing but I don't think I've ever seen one. It may just be that the bottom of the housing is open (so the fusible link is still inside the plastic but not fully enclosed) and I've seen them without noticing the difference.
These are the fuses in modern cars, with 2 blades that insert into the fuse block, and a plastic housing labeled and color-coded for the current capacity of the fuse on the top that also provides a good way to handle the fuse.
Il Carriaggio 1975 Argosy 24 | Il Progetto 1976 Argosy 28 Center Bath | WBCCI# 15566
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Yesterday, I had two circuits out of four working (need three). I switched them and got light to all three units but only on two circuits. Today, I cleaned the fuse block and sanded the contacts. When I reassembled it all, I had one out of four working. A little frustrating. Tomorrow, I'm going to switch them all around again. I'm not sure how to describe what I need while looking for a source for a new block. This panel has four 20-amp circuits, a 30-amp charging circuit (whatever that is), the 50-amp connection for the converter neg & battery pos, and the connection for the battery neg and converter pos. There's another connection with white wires on both sides, but I don't know what they do. Any suggestions?
Well, I think I can close this thread now. With all your help and a multimeter with a new battery, I checked the circuits, and all of them actually were measuring voltage, though the lights didn't work from 1 & 4. Nos. 2 & 3 worked the lights after sitting for awhile after I cleaned and sanded the contacts. I moved purple from #1 to #4, and, what a miracle!, it worked. Now I have three circuits working, even though I don't know why some didn't and then did. I also unplugged shore power for a couple of hours to make sure all went well with that, and it did.
Thank you for your advice. I studied what I found online of available 12-volt panels and may get one in the future, but I guess I'll stick with what I've got for now.
Don't expect that circuit to remain working for very long. The attached photo shows what happens, and it happens rather rapidly.
The heat from the metal which has lost its temper heats up to a surprising (and dangerous) degree. The heat has caused the wired connecting to Circuit #2 to go from purple (or was that the yellow?) to black...
Oh, that looks bad. Why didn't it blow the fuse? So far, mine aren't doing that, but I'll keep a close eye on them. That's easy now, since I removed the dinette and replaced it with the Studio Day Sofa.
Yesterday, I attached the dinette table (cut down to 26 x 35) to the side wall under the two windows and made a table over the wheel well from one of the dinette's lower storage doors (perfect size).
Now I just need to fix the propane line to the cookstove and cover the side opening where the water heater was, and I'll be ready to roll.
A possible sources for excessive heat in wiring is arcing. Most of the time, arcing is casued by a loose connection, but it can also be caused by broken strands in multi-strand wire.
Oxidation can also cause overheating, because the electrical reistance of a copper oxide is higher than the resistance of pure copper or other copper alloys. In the picture, both of the wires with damaged insulation (#1 and #2) show oxidation. It's hard to tell because of reflection off the glass of the #1 and #2 fuses, but it appears that one or both might have blown or is about to if the discoloration on the glass of the fuses is due to melting of the fusible link inside.
Side note, but whenever you use an inline fuse like this, orient the fuse so that the flat part of the fusible link is visible (as on #3 in the photo); it's easier to tell if the fuse is blown that way, than if you're looking at the narrow edge of the fusible link.
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