Electrical question

I have got myself one of those Stebel Magnum horns as my SV's horn sounds like Herbie.

I have read the fitting guide in the FAQ's http://www.sv650.org/docs/FIAMM%20DU...C%20HORNS2.doc - my question is this - what is a relay, and where do i get it from - i understand that it is to stop my horn button from burning out, but how does it do that?

Do i have to run from my live feed on my bike - i have enough stuff attached to my battery - Starcom 1 - and won't be able to get the bolt back on the live terminal!

Can i not just add a relay (whatever it is) in to my existing horn power line, and then install my new horn past that relay?

Hope this makes sense to someone, it doesn't really to me!

Any advice appreciated.

Thanks

[BillyC]

A relay is basically a switch.

But what makes it special, is that it is an electrically operated switch.

This means that you need another switch, to operate the relay - a switch operating a switch! It has two sides - one for the high current, and one for the low current - the side that effectively controls the switch.

They are used to allow very large currents or voltages to be safely turned on and off. In this case, the tiny little switch that operates your horn isn't really capable of handling the large currents that would be required to sound your new equipment.

So, we do a clever bit of wiring, so when you push the horn button, it actually turns on the relay. The relay, now turned "on" completes the switch for the new horn - hopefully making a noise!

The idea is that the horn will feed directly from your battery, through the relay... and with the horn switch now connected to the other side of the relay - to activate it, instead of directly to the horn.


All this horn is making me weary!

Thanks - that makes sense - can i get one from Maplins - do they come in different "strengths" or is a relay a relay?

[TSM]

When i installed my twin FIAAM's on my bike, i first tried it without the relay and the horns made a click sound.

I just went to halfords and bought a Fog light relay kit and used that, mounting the relay between the cylinders (other people mention to mount it under the air box, what ever you find is best and secure).

Saying all that i beleave that Sudox has the same horn as you and he connected it directly to the horn switch without a relay. Ask him.

yes mate they came in different ratings - you want a 12 v dc coil relay with a load rating suitable for the horn ( should be on the horn )

Originally Posted by BillyC

A relay is basically a switch.

But what makes it special, is that it is an electrically operated switch.

This means that you need another switch, to operate the relay - a switch operating a switch! It has two sides - one for the high current, and one for the low current - the side that effectively controls the switch.

They are used to allow very large currents or voltages to be safely turned on and off. In this case, the tiny little switch that operates your horn isn't really capable of handling the large currents that would be required to sound your new equipment.

So, we do a clever bit of wiring, so when you push the horn button, it actually turns on the relay. The relay, now turned "on" completes the switch for the new horn - hopefully making a noise!

The idea is that the horn will feed directly from your battery, through the relay... and with the horn switch now connected to the other side of the relay - to activate it, instead of directly to the horn.


All this horn is making me weary!

Great description mate i`m a sparky and i wish somebody had described them that well when i was at college - many moons ago

Cheers