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Best practices for breakers for marine electronics?
In retrofitting my old (1983) boat, it was set up mostly with one breaker per electronic device. Given the rapidly expanding number of electronic devices, I can quickly use up a lot of panel real estate putting one device on a single breaker. Moreover, the breaker sizes are pretty large relative to current draw (even a 2.5 amp breaker would be difficult trip a lot of marine electronics). So, I'm wondering what is the best way to provide power to a suite of devices. Perhaps one breaker goes to a fuse panel, which then provides power to a range of things you'd likely turn on at once? What do you do? I've not seen this topic addressed anywhere.
Hi Peter, this sounds like what I have done recently. On my GB36 I have linked a DC panel mounted 15A breaker to a 12-circuit BLUE SEA SYSTEMS ST Blade Fuse Block. This gives me 100A per block/ 30A per circuit -- plenty of juice for my electronics including Furuno MFD, radar, sonar, VHF, autopilot, NMEA2K bus, etc.
In use I can flip off the breaker as I leave the boat and know that all of the connected devices are powered safely off. And recently I have seen ST-sized micro breakers that will fit in the blade sockets, so I might start replacing these as well which will give me even more control over the individual circuits.
There are quite a few ways to tackle circuit protection for small load circuits. What Andrew suggests above works well and I'd also suggest you look at the Blue Sea Systems breaker 5050 series of breaker blocks. You can get them in six and twelve circuit versions and they use push button breakers. The breakers are available in sizes as small as 3amps. I've used them a bunch of spots where I know I'm going to have several circuits and want to protect them separately.
This is also an area where digital switching can shine. Options like the Maretron M-Power CLMD12 can be set with virtual breaker thresholds to trip at nearly any amperage you specify. If you just want to protect a few small circuits it might be overkill but if you have switching and circuit protection needs, digital switching can be an excellent option. Here's a story I did on retrofit options recently: https://panbo.com/digital-switching-gets-easier-cheaper-and-more-compelling/.
@ben-stein. Thanks so much for those thoughts Ben - much appreciated! I'm kinda surprised more people haven't chimed in on this one!