During our first season with the boat we had a couple of electrical problems. Investigating these issues brought the overall horrible condition of the boat's electrical system into focus.Dasein suffered from 40 years of neglect and bad practice. The wiring and connections were generally heavily corroded, and much of the newer wiring was jury rigged, consisted of inferior materials, and often completely bypassing the fuse panel. The deeper I dug, the more evident it became that we were simply going to need to gut the old system and start anew.

The battery system was built around the existing (2 seasons old) house bank and internally-regulated 55-amp alternator. To this we added a dedicated cranking battery and a Xantrex Pathmaker battery combiner.

Power Needs

Compared to most cruising boats, our power needs are quite modest. We don't have many high-draw appliances aboard—no windlasses, watermakers, or refers. When we purchased the boat 3 years ago we needed new batteries, so at that time I calculated what I anticipated our power usage to be. I figured that in a worst case scenario—multi-day passagemaking with extensive use of the tiller pilot—we might use as much as 125 amp-hours of power in a day. But for the sort of coastal cruising we anticipated doing I couldn't realistically foresee using more than about 40 to maybe 50 amp-hours per day. And in actuality I expected our draw to be even less. Based on these numbers we decided to install 200 amp-hours of deep-cycle capacity. This wouldn't be sufficient for a full 24 hours worth of passagemaking demands—it is recommended to never draw your house bank below 50% of charge—but would provide us with sufficient power for a couple of days between charges while coastal cruising.

After planning out the system and placing my orders, it was time to get down to brass tacks and strip out the old system. Removal of the old proceeded pretty smoothly with little of import to note. Basically, since I wasn't planning on reusing much of anything, I cut all the wire at the connections and pulled it loose. I then removed the old panel, all the terminal blocks, and miscellaneous garbage such as the battery switch, solar regulator, and the like.

I was careful not to damage the GPS power cord or any of the wiring related to my engine panel, as I did, in fact, intend to reuse those items. I was also careful not to cut the cables running to my instrument transducers. But aside from those few items, everything else going into the new system would be new.

Once all the wire and cable was run, I turned my attention to making all of the necessary connections.This is by far the longest and most tedious aspect of a wiring project. For each connection I had to strip the end of the wire, insert the wire into the correct terminal, crimp the terminal, heat shrink the connection, and screw the terminal to the appropriate buss bar, terminal strip, or breaker.

Subpanel connections

The wiring from the accessory subpanel was all cut short—just long enough to pass through a bulkhead in the galley and reach a set of terminal blocks. There are two terminal blocks to support all the wiring which leads from the accessory panel.