Addition of Air horns (wiring)

Audio, Navigation, Electronic
Post Reply
Rubik
Posts: 116
Joined: Sat Jun 04, 2016 10:22 pm

Addition of Air horns (wiring)

Post by Rubik » Fri Jul 13, 2018 5:46 pm

I have finally got my lovely yellow Cactus back from the repairers. Looking nice until it becomes invisible again and someone kindly bends it again for me.

While they had the front off they kindly fitted some air horns and compressor into it. The compressor is easily accessible under the bonnet. I had these kicking around and want them as a secondary horn.

I told them not to wire it in (keeping costs down) but having bought a push button and a 12v relay to do it myself, I only have one problem.

Can anyone advise how to lead a wire from the engine compartment into the saloon so I can fit the push button switch next to the steering wheel etc? Thanks in anticipation.

Cactus.jpg

Compressor.jpg

Horns.jpg



davew
Posts: 643
Joined: Thu Apr 14, 2016 11:21 am

Re: Addition of Air horns (wiring)

Post by davew » Fri Jul 13, 2018 7:52 pm

Rubik wrote:
Fri Jul 13, 2018 5:46 pm
I have finally got my lovely yellow Cactus back from the repairers. Looking nice until it becomes invisible again and someone kindly bends it again for me.

While they had the front off they kindly fitted some air horns and compressor into it. The compressor is easily accessible under the bonnet. I had these kicking around and want them as a secondary horn.

I told them not to wire it in (keeping costs down) but having bought a push button and a 12v relay to do it myself, I only have one problem.

Can anyone advise how to lead a wire from the engine compartment into the saloon so I can fit the push button switch next to the steering wheel etc? Thanks in anticipation.

Cactus.jpgCompressor.jpgHorns.jpg
You may know all about this but don't forget to add a chunky diode across the relay coil to absorb the relay back emf generated when the relay coil energising circuit is opened when you release the button....
If the relay coil connections have polarity markings then a diode is probably included anyway.

BTW have you considered the possibility of using a wireless doorbell scheme to actuate the relay ? One reservation about such a scheme would be the possibility of RFI susceptibility issues...


Rubik
Posts: 116
Joined: Sat Jun 04, 2016 10:22 pm

Re: Addition of Air horns (wiring)

Post by Rubik » Sat Jul 14, 2018 6:59 pm

davew wrote:
Fri Jul 13, 2018 7:52 pm
Rubik wrote:
Fri Jul 13, 2018 5:46 pm
I have finally got my lovely yellow Cactus back from the repairers. Looking nice until it becomes invisible again and someone kindly bends it again for me.

While they had the front off they kindly fitted some air horns and compressor into it. The compressor is easily accessible under the bonnet. I had these kicking around and want them as a secondary horn.

I told them not to wire it in (keeping costs down) but having bought a push button and a 12v relay to do it myself, I only have one problem.

Can anyone advise how to lead a wire from the engine compartment into the saloon so I can fit the push button switch next to the steering wheel etc? Thanks in anticipation.

Cactus.jpgCompressor.jpgHorns.jpg
You may know all about this but don't forget to add a chunky diode across the relay coil to absorb the relay back emf generated when the relay coil energising circuit is opened when you release the button....
If the relay coil connections have polarity markings then a diode is probably included anyway.

BTW have you considered the possibility of using a wireless doorbell scheme to actuate the relay ? One reservation about such a scheme would be the possibility of RFI susceptibility issues...
Funny you mentioning that, a friend had already suggested connecting it wirelessly but my only worry would this loud airhorn sounding sporadically, not a 'ding-dong' when Avon is calling.


davew
Posts: 643
Joined: Thu Apr 14, 2016 11:21 am

Re: Addition of Air horns (wiring)

Post by davew » Sun Jul 15, 2018 9:01 am

The scheme I had in mind would be with a wireless link by using something like this ebay item 323246230762 or similar.

According to the description, an internal jumper at the receiver allows it to be used in what they call "Jog" or "Inching" mode which seems to be control button down for "ON" and button up for "OFF".

Not a lot of money for this gadget, but I'd agree that if you can find a convenient route for a single wire connection to the relay, that would be the cheapest and simplest way.


Post Reply

Return to “Electronics and In Car Entertainment”