Harbor Freight air horns. I need help.

[SouthernBrandt75]

I am far from an electrician and the instructions are lame. Are there any electricians that could help.

[VileZambonie]

As in you want to hire an electrician? lol

Where are you stuck?

[SouthernBrandt75]

You close to Olympia?  Lol.  Where the wires go on the resistor.

[Irish_Alley]

resistor or relay?

[Irish_Alley]

http://www.harborfreight.com/12-volt-super-loud-air-horn-40134.html
if its this setup its a spst



the easiest way to think about it is theres a coil/electric magnet in the relay (post 85 and 86) one side will be 12v from a switch while the other will be ground. post 30 will be a fused 12v supply from the battery (not fuse box but battery due to higher amps) and post 87 will be the air compressor. once you put power to 85 it will turn the magnet on and pull the tab to open to closed and will complete the circuit and give the air compressor power.

ive had cheap relays stick on and burn up wires make sure you have an inline fuse of one sort or another

[SouthernBrandt75]

Can I just hook the wires off The existing horn to the post that say to hook them to on the relay?

[SouthernBrandt75]

http://m.harborfreight.com/three-trumpet-12-volt-air-horn-set-with-compressor-94862.html

It's this one if it matters.

[Irish_Alley]

the electromagnet part of the relay can be wired up with 85 coming from the hot wire to the stock horn and and 86 going to ground. but the other wires have to go the way i said before. the stock wires on your truck may not hold up to the high amps the air horn will draw 

[SouthernBrandt75]

87 amd 85 I have hooked up. 87 to the compressor + and also the side post + that goes to switch for music or just horns. And 85 is grounded to body. Now where i get lost is i should put 30 to the battery with an inline fuse and the last to the either the - or + on the horn? Also with the dual horns on my truck which is The negative and which is The positive? Sorry for so many questions and thank you so so much for the help.

Trey

[Irish_Alley]

30 = battery fused
87 = Compressor +
85 = Switch (horn hot wire will work)
86 = Ground

[Irish_Alley]

i will also say this getting to know these things can be a challenge. cause theres a few different types of relays there spst (single pole single throw), spdt(single pole double throw), dpdt (double pole double throw) and dpst (double pole single throw) theres even tripple and so on but these are the basics

the "pole" refers to how many circuits it can control a SP would be this that youre working on while a DP would be a relay that could turn on both the air horn and your lights or what ever. but the two different poles will work together like if they were mechanically tied together. you turn one on the other comes on also

the "throw" refers to how many actuator positions relay will have. a ST is the relay you have theres an off and an on much like a house light switch. a DT will have another terminal on the relay and when the relay isnt getting any power to the coil it will have the power going to 87a (normally closed) then once the relay gets power it will flip the adulator to the other post 87b (normally open). these are good if you want to keep your original headlights hooked up and have the headlights on the 87a (normally closed) and the off road lights on the 87 (normally open). this is good for plow trucks, you would flip the switch to power the relay and the power would be diverted from the stock headlight and just to the off road lights.

i hope this doesnt confuse you. but if you have a question i can try to clarify it or someone else can

these are SPDT. they are just like youres except the 87a. you dont have that post but its the same idea. 87a is the resting spot on the relay

[SouthernBrandt75]

Well my friends I did it!!! First try. Sounds good too for the price I paid. Thank you to everybody. I still don't get relays lol.

[Irish_Alley]

even though i do get them i still get lost and have to think about what im doing. i have a project for my sons power wheels, its originally a 6v system so the top speed is only 2.5 mph, i added a 12v battery top speed is now 7 i plan on making it 18v but you cant just apply 18v to the 6v motors so i need to wire up a few relays and times to get it to work right and go 2.5 mph to 7 then to 12 mph

[SouthernBrandt75]

Well talked too quick. Lol. Cheap ass relay ugh

[Irish_Alley]

lol did she get stuck on