Electrical Question

[jb]

Installing a horn on the boat, 12v, two wire.
Horn button is the the interrupter on the circuit.
I'm sure it would work on either wire (red or black)
but which wire is the proper one to break, red (+) or black (-) ?

[BarryBobPosthole]

red and if you have a 12 v fuse, I’d put it in serial too.

BKb

[Thumper]

Red (pos) wire Bubba. Fuse it also or better yet, install a horn relay in the circuit if you have much of an amp draw. (a decent horn usually has a pretty heavy draw and you could start burning up switches)

[Thumper]

Sorry P-hole, I read the question on my phone downstairs and waited until I got to my office p/c to answer. I didn't notice you'd answered already. At least it appears we finally agree on something! :laughing

[jb]

splane this to me Lucy, fuse between battery and button ?
What amp fuse?
What's "put in serial" ?

[Thumper]

I ALWAYS install a relay in a horn circuit, but if you simply fuse it, I'd start with 15 and go to 20 if you have to. Use the proper gauge wiring. We have salt here so I always use a marine grade wire, but with your fresh water, regular automotive wiring should be fine. Hook your fuse holder to the positive terminal of the battery, run your red wire from the fuse holder to your switch, then from the switch to the pos. side of the horn.

[Thumper]

Here ya' go Bubba ... I just asked my good friend Google and came up with this. ;)


How to Wire a Boat Horn

https://ourpastimes.com/wire-boat-horn-8520476.html

A horn provides an audible method for alerting other boats or swimmers to your presence. They are necessary for safe operation of any vessel in all waterways. Wiring for a boat horn is a simple electrical circuit with a switch. Protecting the wire connections from the elements with a tight wrap of electrical tape assures they don't corrode due to water penetration. Installing a boat horn is a simple process once you understand where to connect the wires.

Strip 3/8 inches of insulation off the horn's positive and negative wire with wire strippers.

Run a section of black wire from the horn to the boat's battery and cut to length. Strip 3/8 inches of insulation off both ends of the wire.

Connect the black wire to the negative wire at the horn with a butt connector. These work by placing one wire in each end and compressing with pliers.

Loosen the negative terminal on the battery. Slide the black wire underneath and tighten it down.

Run a section of red wire from the horn to the switch, then to the battery and cut to length. Strip 3/8 inches of insulation off both ends of the wire.

Connect the red wire to the positive wire at the horn with a butt connector.

Loosen the two terminals on the switch with a screwdriver. Cut the red wire at the switch's location and strip 3/8 inches of insulation off the end of both wires.

Connect one wire to each terminal on the switch and tighten them down.

Connect the red wire at the battery to the fuse holder with a butt connector. Loosen the positive terminal on the battery and slide the fuse holder's wire underneath. Tighten down the terminal.

Install the horn manufacturer's recommended size fuse in the fuse holder by pushing it in.

Wrap all of the connections with electrical tape and secure any loose wires with cable ties.

[jb]

thanks, never even thought to look it up, Old Al should be damn proud of what he invented.

[Thumper]

Why would you ever need to look anything up with the G/H crew at your beck and call? :huh