Hi first time poster here,

I have a few questions, I have planned to put together a small and cheap electronic relay circuit to power a hooter for my local touch football club using 2 small relay boards (see below link). Everything in the relay circuit works correctly and i have tested it with a 12v pc fan. I picked up a twin 12v air horn set that would usually be installed into a car to use as the hooter, however I neglected to take into account how much current the hooter compressor would draw (around 8amps). My 240v AC - 12v DC power supply only provides 1amp. As i have limited electronics knowledge and this was more of a project for myself, I now need to find out how/if I can provide about 8amps to power the compressor.

I started doing a little research and found a DC-DC booster which can apparently increase the voltage as well as amps(see below link). I would only need to maintain the original 12v DC voltage and increase the amps with the on board dial. This sounds too easy... maybe I am over thinking it.

If I were to replace the hooter with something that has a lower amperage draw, It would need it to still be loud enough to hear possibly a few 100 meters away at distant fields.

Final points

• Is a DC-DC booster a viable option
• Will finding a power supply with a higher amp output cause damage to my circuit
• Can a capacitor be implemented into the circuit which the compressor can draw from to run

I am open to all ideas and suggestions. Sorry if I come across a bit silly, but I am still only very new to the electronics world. Any help will be much appreciated.

References:

• Relay board - http://www.dx.com/p/produino-12v-di...n-time-delay-relay-module-301860#.VRPFhjTLeKM
• DC-DC Booster - http://www.ebay.com.au/itm/DC-DC-60...upply-OK-/281613871859?_trksid=p2054897.l4275
• Air Horn Info - https://www.rivcoproducts.com/instructions/download/Air Horn wiring and troubleshooting booklet.pdf
  

Cheers

Pat

 

Power in = Power out minus losses. If you boost voltage, you unboost current. If you boost current, you unboost voltage such that the product of Vin*Iin > Vout*Iout. (Laws of thermodynamics cannot be violated)

Me thinks you need a bigger power supply, or a big lead-acid battery. You can charge a big battery with your 1A supply as a charger; it just takes longer...

 

Ok no worries, thanks for the reply. So if i was to get a 12v power supply that was say 6-8 amps that should do the trick.

 

If the hooter compressor draws around 8A, you need a supply that can supply 8A or more. 6A won't be enough.

 

Ok no worries, thanks for the reply. So if i was to get a 12v power supply that was say 6-8 amps that should do the trick.

How often, and for how long are you using the horn.?

If you are using a 12V Sealed Lead Acid battery of about 5Ah capacity, allowing for losses, you could operate the horn for a total of about 20min before the battery needs recharging. I am assuming that the battery is not being recharged during the game (no ac available), and would be recharged at home in between games...

I would need to know more about your 1A supply to determine if it is suitable as a battery charger or not...

 

Why don't you get yourself an air pig and just carry it around in a duffle bag? No compressor or electrical stuff to worry about. (Former hockey and soccer coach )