Do i need a relay for an air solenoid

[Rammstein1224]

Hey guys im piecing together an on board air system and train horns and i bought a wolo air solenoid and i was wondering if i would need a relay for that or if its ok just to connect right to the horn switch?

[NoRalPh]

That solenoid really is, sort of, a relay anyway. If you took the wire going to the horn itself (Y/Gr?) it's already gone through the trucks relay of course too.

Remember though, the Horn SW in the wheel is probably supplying Ground to that relay.

[Rammstein1224]

Thats kinda what i was thinking too. im activating it by the stock horn button using the cords i snipped from the stock horn assembly

[ZMANN]

looks low amp so I agree

is the OEM horn a - signal ?

[Rammstein1224]

Originally Posted by ZMANN

looks low amp so I agree

is the OEM horn a - signal ?

Well i powered a direct drive air compressor with the wires from the OEM horn and it worked just fine. but thats also not holding back 120 psi of air

[JSchuricht]

It really depends on the solenoid. The ones I use are air actuated so basically a few hundredths of a amp to control a really small solenoid that pushes a piston for a larger solenoid. Some larger solenoids require more current but most would hold up fine. Just check the requirements of the solenoid if your under 5a I doubt you would have any issues.

[Rammstein1224]

It says the solenoid current is 300 mils what does that mean?
http://wolo-mfg.com/804-big.jpg

[JSchuricht]

It sounds like their saying it's 300 ma or milliamp in which case it's 0.3 a so you should be just fine.

[Rammstein1224]

Originally Posted by JSchuricht

It sounds like their saying it's 300 ma or milliamp in which case it's 0.3 a so you should be just fine.

Sweet thank man i figured it should be fine