Recently installed my trian horn, and the air compressor keeps melting everything I hook up to it. Tried straight to the battey, key on fuse, and a separate battery. Many sizes of large wire have been melted. I'm dumb at this stuff so any advise or what I'm doing wrong would be greatly appreciated. The air compressor is really small, I wouldn't think it would need that much electricity, especially with the install kit they send with it. It's an ebay special 300$. Maybe that's the problem???

 

Melted wire means that the current needed to run the compressor, exceeds the ampacity of the wire you are using. Is there a number plate on the compressor that says what the current rating is? What size wire and fuse are you using now?

 

They sent some small wire and a five amp fuse. I have more than doubled the wire size and it instantly blows the fuse. Hooked direct. It melts any size wire.???

 

The dc motor or the compressor must be seized.

 

The compressor runs fine. Fills up,kicks off when full and refillls after a couple blasts. Do I need a relay type thing? Or could I wire a plug on it and run it through my power inverter?

 

Is there anything on the compressor that tells you what the AMPS are?

 

humm.......so how long does it take to burn up the wire?

and no on the inverter. It is a DC motor...your inverter puts out AC (kind of)

 

If it does not have a relay then it absolutely should have one unless the pressure switch is rated for the higher amperage.
I have a compressor for my airbags and have it hooked up with a 25a setup. 5 seems really low for a compressor no matter how small.
What gauge wire are you using? I would think at a minimum 12-14ga for a compressor and a good fusable link.

 

Tyler I just finished installing my train horns a couple of days ago so maybe I can help?
I ran #12 wire from the battery to the relay that was included in my kit. (I also fused the wire with a 25a fuse at the battery). You should have gotten a relay in your kit, if not you need to contact the seller and have them provide you with one.
This is how I installed my system:
(I ran #12 wire directly from my battery to the relay) The -12v wire from my battery went directly to the motor and the +12v went to the relay. Another wire from the relay goes to the motor. There is also another wire from the relay (#14 wire) to the button in the cab to activate the compressor. There is also anothe wire from the relay that went to the pressure switch on the air tank.
The two wires from the horn go to the button to activate the horn. The horn switch gets +12v on one side the other goes to one wire of the horn solenoid and the the other wire from the horn solenoid went to ground.
I used two switches for my system one for the compressor and one for the horn. You dont really need the second switch for the horn but I dont want to blast everyone off the road when I just want to honk at them!!


Here is the diagram and instructions from my kit!

Instructions
When you first install the train horn system, turn on the air pump and allow it to fill the tank until the pressure switch turns the pump off. Do not let it exceed 125psi. Now you can test your horn! Remember, the air compressor is not designed for continuous usage. The air pump needs time to cool down between the horn blasts. If you plan on using the horn every couple of minutes, you need to seriously consider purchasing a very large air tank.



Operation
Power from the toggle switch to your air pump should only be turned on after you have honked the horn a couple of times. The compressor does have an automatic shut off pressure switch, but should that switch fail or a leak arise, the pump will run continously and will drain your battery or cause premature failure of your pump.
So remember to turn the toggle switch on, let the pump run until the pressure switch cycles off your pump, and then turn off the toggle switch. You will be able to tell when the air pressure is low and you need to turn on the compressor again.

All Kits require a Relay.
Relay Terminal numbers are on the bottom of the relay. You must unplug the connector to see the numbers.
Install the gauge with teflon paste or tape.
Relays, pressure switches, and inline fuses can be purchased separately.

 

Nick was correct. A melted wire always means that there was too much current flowing for the size wire that was used. A general rule of thumb is 16ga wire - 10amps, 14 ga wire - 15 amps, 12 ga wire - 20 amps, 10 ga wire - 30 amps. If you use a fuse rated for the size wire, you will not burn the wire. The compressor more than likely has a tag somewhere on it telling you the voltage and amp draw under full load. If this is one of those "made in china" deals, make sure that it is for a 12v system and size the wire for the amp draw listed. If it still blows the fuse, the motor is bad. The wiring method that red boat used is also correct. The wire that is labeled 12V fused going to the switch, is the circuit that activates the relay. That circuit draws very little amps and is probably what the 5 amp fuse that was provided in your kit was originally intended for. According to the drawing, the hot wire from the battery to the relay is fused at 30 amps, so, by the NEC, it should be 10 ga wire. Hope this helps.......mike

 

sounds to me like a short. If it was motor draw it probably wouldn't burn things up so quick.

You stated it runs fine ( Fills up,kicks off when full and refillls after a couple blasts), when is this? What are you changing that makes it smoke wires and fuses?

 

I REALLY don't understand the "connect to a good ground" lead on the SPDT switch.

Like, Huh??

Pop

 

Must be an illuminated switch.

 

That would make sense.

How shown, however, it's confusing a bit.

Our dialog should clear it up for anyone who comes across the drawing.

Pop

 

Yes the ground is for the illuminated switch, sorry if I caused any confusion on that