Fuses

[estrst25]

Could someone please recommend what size Fuses would be appropriate for the items I will be installing.
1. Radio
2. Fish finder
3.12v outlets (one cigarette plug, USB. ) can I tie these two together or should they be on individual fuse and switch?
4. Running light and led strips on front(red, green) also, is it OK to tie these two together as well. Thanks in advance

 

[richg99]

My simple fish finder uses a 3 amp fuse. Yours may differ. Check the manual.

Your radio manual will show what amp size fuse you need. That could be a big range, probably starting at 5 amp minimum.

The outlet fuse size would depend on what you are going to plug into it.

The length and size of wire that you used to connect all of these things will be a determining factor on how much current you are able to use, too.

There is a wire size guide on this LINK...
https://www.minnkotamotors.com/Support/Battery-Selection---Rigging/

richg99

 

[DaleH]

Radio - What kind? VHF radios are <= 1-amp in standby/monitor and ~7 when sending. The unit manual will specify it.

Accessory Outlets - I'd size it to the biggest amp draw item likely to be inserted, e.g., 55-watt handheld light or similar. But heed Rich's advise to make sure you also have the proper wire, as fuses are there to protect the wire (and your boat) from burning, not primarily to protect the device per se.

If using watts rated items, divide wattage by 12.6 (for nominal DC voltage) to get amps. Equation: Amps = Watts/Volts DC, so for that 55-watt light, the amps are 4.3, so size 5 or 7.5 or so, IF the wiring can handle that ampacity (amp capability for the length of the run).

Also note some items have an initial/peak amp draw when 1st switched ON that exceeds the typical draw, but that tends to be for larger items like starter motors et al ...

 

[RiverBottomOutdoors]

Follow their advice on fuse sizing. Make sure fuse is close to power source (battery).