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Old Oct 20, 2007 | 11:08 AM
  #1  
Neal 97 250's Avatar
Neal 97 250
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From: Johnson City, TN.
Relay Question

I know what relays are and what they do. I am just not too smart at the diagrams. This is a relay that came with the ViAir air pumo I bought off ebay so it didn't come with directions. I have a pump, presure switch ( on @ 120 - off @ 150), and this relay. The pump has a black wire with a ground connector and a red wire with a female flat connection. In what order sould I wire the pressure switch and the relay. Also the relay has 4 connections What do I do with each, as I am not smart with the markings on the relay?

Thanx,
Neal

 
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Old Oct 20, 2007 | 11:16 AM
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Damn, I cannot remember at all! hahaha.

Basically you apply power to one side and it closes the relay on the other.
As for voltage through the relay i'm unsure.

I really do not understand relays very well. I think i was absent for that class.
 
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Old Oct 20, 2007 | 11:24 AM
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85 and 86 is the coil.
30 and 87 is the switch.
Use your pressure switch to power the coil.

Bill
 

Last edited by MADVAN; Oct 20, 2007 at 11:26 AM.
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Old Oct 20, 2007 | 11:33 AM
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yep like Bill said 85 and 86 are the signal side. So I would run power to the relay in at 86 then out to 85 to the pressure switch then ground the other side of the pressure switch to chassic ground. Then battery power to 30 (heavy gage for the pump power) then out 87 to pump power lead.
 
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Old Oct 20, 2007 | 05:05 PM
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Neal 97 250's Avatar
Neal 97 250
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So I put the pressure switch on the ground side of the relay switch and not the power side? Then High 30 AMP (fused) to 30 and out 87, 30 AMP to power moter?

What gauge wire should I use for the 30 AMP side? Is 18 enough, IMO I don't think so. I would guess 12 AWG.
 
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Old Oct 20, 2007 | 05:20 PM
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Maybe even 10 AWG for the pump. I am not sure what the standard is for amperage draws but you can't go wrong going big.

The pressure switch can be a power or a ground but most switches last long is they do grounding duty rather than power duty.
 
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Old Oct 20, 2007 | 05:26 PM
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Put the pressure switch on the ground side of the relay. That way when pressure gets low and the switch closes it'll ground that terminal of the relay to energize the coil. Then the switch will close and supply power to your pump. Per this table:

http://www.powerstream.com/Wire_Size.htm

12ga wire would be plenty but you could go as small as 14ga.
 
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Old Oct 20, 2007 | 06:06 PM
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Good link Powrstrkr! Thats the type of info I was hoping somebody would have. link saved, reps sent!(edit- I tried but gotta spread the love)
 
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Old Oct 20, 2007 | 06:15 PM
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Not necessary but thanks just the same TJ!

Let us know how it works out Neal.
 
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Old Oct 20, 2007 | 10:00 PM
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i saved the link also and successfuly reped ya good info
 
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Old Oct 21, 2007 | 10:10 AM
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Thanx guys. I will be out of touch for a couple of weeks. Going camping and working out of the camper so not much internet. I am hoping to do this while I am gone but still looking for 8" tanks. More places mean more junkyards.

Reps sent also Thanx again.
 
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