36v horn

[wurly]

On a car, these things are usually switched on a by a relay. The reason they do this is to prevent the contacts welding themselves closed (there is too much current going through the tiny switches on steering wheels or steering columns). So the live feed is through a fuse then through the heavier contacts of a relay. The tiny horn switches (on a car steering wheel) will connect(energise) the relay coil to earth switching on the horn. A heavier push button momentary switch like you would find on an old motor bike will be fine if you don't want to wire in a relay.

 

[103Alex1]

On a car, these things are usually switched on a by a relay. The reason they do this is to prevent the contacts welding themselves closed (there is too much current going through the tiny switches on steering wheels or steering columns). So the live feed is through a fuse then through the heavier contacts of a relay. The tiny horn switches (on a car steering wheel) will connect(energise) the relay coil to earth switching on the horn. A heavier push button momentary switch like you would find on an old motor bike will be fine if you don't want to wire in a relay.

Interesting - never knew that. The guy I asked to confirm switch suitable was told about the setup and the 36v battery and seemed to think it would be fine just to wire up using the method he described but I don't understand what that means in terms of what wires go where.

The switch is of the heavier push button motorbike type you describe. It's usually found on KTM and Suzuki dirt bikes, takes high current (up to 10A) and was nearly £30 so I am pretty sure it's up to switching on a horn without a relay - but need to work out how to hook it up in terms of wire sequencing from the info in previous post I don't have a frame ground - there is a 2 x 4-Way BUSBar block, one terminal of each returns to battery negative.

 

[Alan Quay]

To use for horn, take 36v feed from fuse box to one side of switch. Other side of switch to horn +, horn - back to 0v.

 

[103Alex1]

Thanks a lot Mike.

Actually just back from trying it the other way round, after getting impatient for a change lol. It actually did also work with kill LIVE to BUSbar, kill 0V to horn, +ve from fuse box to other horn terminal) ... and doesn't seem to matter which horn terminal is used for +ve and which for 0V . Guess this way means the switch doesn't need to carry any current and is just a circuit breaker.

It's VERY LOUD ... almost need ear defenders at close range ! Genuinely must be over 100dB. Be better outside - going to position it behind the seatpost facing right, bolted to the rack arms as being about the only place it'll fit on my bike without getting in the way of something or other.

 

[Alan Quay]

It will work like that, but switched 0v is less conventional. Will be same current no matter where it is in the circuit though!

A simple switch like this doesn't really have a polarity - its just connecting two bits of conductive material together, similarly to touching two wires together.

When used as a kill switch, it will short the high voltage that feeds the spark plugs down to 0v, thus killing the engine.

 

[103Alex1]

Still learning so much off doing this conversion - was almost all complete gobbledegook when I put in the order for those parts in January and never really believed I'd get all this sorted out on top of the basic motor & controller. Starting to understand the scope of what you can rig up now (it's not scary when you understand the basics of how). Also learned how to test stuff and build the circuits - although much of the electrical theory is still very sketchy. Nothing like actually doing something to help it all start to finally make sense though. Thanks a lot for helping - it's a whole new world .

 

[Scimitar]

I
When used as a kill switch, it will short the high voltage that feeds the spark plugs down to 0v, thus killing the engine.

It can either earth the primary on the coil(s) or simply cut off the ignition 12V source, depending on complexity, and we all know the Japanese love a bit of complexity on their wiring systems.

 

[Alan Quay]

This one is a push to make switch, so designed to short, but you could be right about it shorting the primary.

 

[103Alex1]

This is still going great and really useful before very sharp (and slow) blind corners on my way home in daylight when I always toot a horn even in a car. I was looking under a (car !) bonnet today and realized it's as loud and about the same size.

Seeing this reminded me ... a very expensive looking option for those not looking to wire one in to run off their bike battery :

Loud Bicycle | Car horn for bikes

 

[stesteste]

quick update on the horn i fitted ..yes its loud i probly use this everyday so much traffic with no regard to cyclists best ever used item ive fitted for few quid highly recommended doing ...

 

[103Alex1]

^^ Agree !