I should have stated that I do not like 1-2-All switches and will always remove them and put in separate on-off switches for the house and start batteries with one separate switch to parallel the two. It gives me some more peace of mind that I know exactly what is set for what. A 1-2-All should do the same but switches do fail at times.
I always, always, always turn off the start switch when at dock or on the hook. I will turn it on if I think I might have to raise anchor in a hurry, e.g. big winds expected, other safety
issues like dragging boats nearby, poor holding, etc. I think you need to assume something may happen and manage the risks from every angle.
My house side is completely fused or has circuit breakers on every single
wire and with smaller fuses
whenever a circuit goes from a big fuse/big wire to smaller ones. The other thing that gives me more peace of mind is to go around and check all terminals/cables/wires to make sure they are tight and in good condition (both positive and negative sides). I do this more often for the bigger cables
. The alternator
and starter get special attention since they have big wires in a vibrating environment
. I have rewired a couple of boats which burnt up all they engine wiring from loose connections to the engines. Luckily they did not burn up their boats.
I will always, always, always turn off my windlass
and after raising the anchor. That will prevent a big problem for the large current
device that is in a harsh wet environment
. I can keep the house switch on (if I want) even though the windlass is isolated.
I turn off my propane
solenoid switch after shutting down the stove. I will turn off the propane at the tank whenever I don't need to use propane for any length of time.
AC systems are the most common source of marina firs to my knowledge. Certainly the big majority in our marinas
in town (we have many hundreds of boats here) have been from AC systems. The shore power cord/dock pedestal
is a cause of some of them. It is a very poor system so I inspect my SP cord often and make sure it feels snug in the pedestal
and on my boat. If it is loose at the pedestal I won't use it. My marina is super safety
minded and will replace any plugs if bad immediately. Marinas
I travel too are a different matter so I always check them carefully for a good solid connection, correct voltage, polarity, etc.
In other words, safety from electrical fires involves far more than just whether you turn off the house switch or not. They can happen when you are sailing or motoring just as easy as when you are in a marina. If anchoring
you have to keep at least one battery on for anchor lights (unless you have a reliable and properly displayed solar
or battery light). And bilge pumps should always be on in any situation. On my boat anyway.