Question: I’ve been attending the fall boat shows, and the photo below shows a panel on one of the new boats I checked out. In general the panels on the new boats seem to be smaller than the panel on my old boat, and it’s unclear to me where the builders now hide the fuses or circuit breakers on these new designs. Any insight here would be helpful.
Answer: Great question and no, it’s not your imagination, the electrical panels used today are much more discreet than those on boats five or ten years older. There are two reasons: marketing perceptions, and advances in engineering and available components.
To answer the marketing perception part of the equation, I’ve asked boat salespeople point-blank about this trend and their explanation has been quite believable: People just don’t like the “techy” look of the traditional C-series circuit breakers staring them in the face, in either a rocker switch or toggle switch configuration. Personally I like the techy look, but I am apparently the exception to the rule.
On the technical side of things, engineers have been able to conceal all of the requisite over-current protection, either in the form of fuses or circuit breakers, by utilizing some really modern devices common to the automotive industry.
The photo below shows the back side of a panel similar to the one in your photo above. Integrated onto the printed circuit board are holders for the ATC fuses shown in the photo (yellow and blue, numbered 10 and 15). These have been widely used on cars and trucks for years now, and they represent a significant cost- and space-saving way to provide the needed circuit protection that is both serviceable and out of sight until you need to deal with it.
As a point of comparison, the photo at right shows a line-up of C-series toggle-type breakers on the back of a more traditional panel. Each breaker is easily ten times the size of the ATC fuse that replaces it.
In the same vein as the ATC fuses, we are now starting to see ATC-type circuit breakers being employed as shown in the photo below. For me these are the ultimate in cool-tech as they can be reset if they trip—and you don’t need to keep a pile of spares on board.
ATC-type circuit breakers are available in three varieties, but only the type 2 and type 3 units are compliant with industry standards. The type 1 units are auto-reset, which is not standards-compliant. The type 2 units cannot be reset until the fault that tripped it is corrected. The type 3 units can be manually reset, but will trip again if the fault still exists.