New Electrical Panels

I have recently installed new and relocated electrical switch/metering panels and the information herein may be useful to others thinking of a similar project.

My 32 hull number 27 was built in late 1988. Like others of its vintage the electrical bc_electric_panel.1panels were part of the fold-down helm assembly. The DC panel was on the inboard (port) side and the only metering was a small round analog volt meter. The AC panel was low down on the aft face of the helm assembly. This panel had no metering and was actually tilted toward the floor making access and reading switch labels difficult. I have owned the boat since 1992 and had made a couple of small previous changes. For the DC I had added a digital voltmeter below the panel and used the spare breaker positions for additional electronic equipment circuits. For the AC I had added an analog amp meter above the panel and used two spare breaker positions to split my electrical outlets throughout the boat from one to three circuits. I had also added a galvanic isolator to separate the AC and DC ground systems.

The following factors caused me to revamp the whole system. On both the AC and DC panels the common side of the breakers were connected by a copper bus bar arrangement that made it very difficult to change a breaker, and my breakers were beginning to fail due to age and full time liveaboard use. Last winter I had a melt-down of some wiring in the AC panel that could have caused a fire. Although no visible corrosion was present a crimp apparently overheated, melting insulation back up the wire to where the wire touched another wire. All AC wiring was excessively crowded with the neutral (white) and grounding (green) busses all jammed together with the hot wire (black) breakers behind a poorly designed safety cover. As mentioned above there were also accessibility and metering deficiencies. After many weeks of thinking I decided bc_electric_panel.2to install relocated and completely new panels in a manner that would involve purchased parts and materials, but minimal labor effort that could all be done by me to avoid boatyard labor costs.

Many good companies make boat electrical panels. I chose PanelTronics (paneltronics.com) because of their reputation, excellent printed catalog for detailed study, and their wide selection of semi-custom panels and enclosures. I wanted an upside-down version of their #3401 to have the AC section over the DC to minimize the crossing of wires when I extended circuits. They accommodated this by selling me a #3305 AC over a #3203 DC panel both in the same metal box enclosure. There are thousands of switch labels to select from and PanelTronics did this just as I specified for each breaker location. The aluminum enclosure and panels are nicely finished matte black, the panels hinge down for access, and a smoked Plexiglas hinged cover protects the front. I had to use a metal holesaw to cut eight one-inch wiring access holes (protected with rubber grommets) in the right side near the rear.

bc_electric_panel.3The new enclosure is mounted to the left of the fold-down helm assembly; the top being about 10 inches down as my auto pilot controls are already there. I removed the old DC panel and cut the fiberglass helm assembly so wires could be mounted on the bulkhead and the helm assembly still open and close. About half of the DC wires went down to the engine space and these were long enough to route to the new panel by shortening and adding new lugs. A new wiring harness was made for those that had to route from the panel to the helm assembly. The AC common busses for the neutrals and grounding wires were moved from the helm assembly to the bulkhead in the same area but lower down. This gave extra wire length to better space these busses and clean up the wiring with new terminals. Single “unified” neutral and grounding wires were run to the new panel. For the hot side of the AC circuits all wires were extended with carefully installed butt splices going up one wire size. A small terminal board was installed on the bulkhead for the incoming shore power and this then extended to the new panel. For safety and to satisfy surveyors all this AC stuff is covered by a removable panel having “DANGER 120VAC’ in red letters.

A few other details: Although the new system has full digital metering, I found it a pain to come from the forward cabin to the pilot house to check DC volts which I often do in the night or early AM as I live for days at a time at anchor or on a mooring. I cut a two-inch hole in the left side of the enclosure and installed my old digital DC volt meter there so I can check this critical reading by just sticking my head around the corner. The new panels came completely pre-wired, but the best folks can make a mistake. The metal panel itself was grounded with a small three-inch jumper to the white neutral bus rather than the green bus. I called them about this and made the change; they asked for the initials of the QA inspector on the QA sticker! I ordered from PanelTronics plain matte finished black panels to cover up the areas of the old breakers; this being important especially on the left side of the helm assembly to provide strength.

Cost was a bit over $1,500 for the panels/enclosure and about $500 for miscellaneous stuff. A ratchet type wire crimper is a must to get proper safe crimps.

If anyone wants more detailed info or wants to see this installation I can be reached at bob@calves.name or at 703-408-2693.

Bob Calves
Diamond Sea – NT 32-027
bob@calves.name

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