Triple Air Horns

[Guest j_mchattie]

Ive got some triple air horns, because the standard alarm horn is pants.

 

I think I need to wire-in a relay (supplied) to the existing positive and negative output from the alarm module (which would supply the standard horn).

 

My air horn compressor needs to be fused to 20A, but the car alarm horn is fused to 15A. Does this mean I can skip the whole relay idea, and just connect the existing horn output (from the alarm module) to my compressor (easy option)?

Or will i need to incorporate the relay?

In which case, would the alarm module output kill my relay? Would it be the whole 15A across the relay low-current circuit?

 

well...... this is the technical section!

 

Thanks for your help!

[Guest j_mchattie]

It looks like fuse 25 supplies the existing standard horn. The fuse is rated to 20amps, which means I can just use the existing supply leads, and stick them straight onto my compressor. No Relay, no fuse - its all there.

 

Am I right (the TIS isnt great for the 93 mondeo wiring diagrams)?

[Ivor_E_Tower]

Does the existing horn work through a relay? If not, and it is low power then the airhorns may cause the horn switch to burn out (arcing - could be dangerous) - this is despite the fuse having an "acceptable" rating.

[johnb80]

The biggest problem you will suffer if you don't destroy the electrics feeding it is the destruction of the air horns compressor. The compressors are not meant for a duty ratio like they will get in this application i.e. sounding for several minutes. It is also very likely to flatten your battery PDQ. Get an electronic siren, they're much more suitable, won't burn anything out and are still very VERY loud.

 

(This is not me BTW)

 

Regards - John

[Guest j_mchattie]

The alarm goes on then off then on then off then.... over and over again for 30 seconds.

 

I think ill install them with a relay so that the pulse flicks the relay on and off, and the compressor can draw its 30A if it likes