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Final question about relay/hobbs wiring

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Old May 21, 2012 | 08:39 PM
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Default Final question about relay/hobbs wiring

So, putting the final touches on my dual pump wiring and here's where I am. My relay has 5 prongs labeled 30, 85, 86, 87, and 87Q. I'll post a diagram below.
I take it 85 is still the relay ground going to the Hobbs switch
86 is going to be my "key on" power source, probably from the alternator?
And 30 is my power wire coming directly from the battery.
But the rest are different. So where do I wire my power to the pump in the slot labeled 87 or 87Q?

So then comes the hobbs switch. It has 3 prongs coming out of it. It is also pictured in the diagram below. They are labeled NC2, NO3, and COM. My guess would be that the ground coming from the relay goes into NC2 and the ground is completed with the COM prong.

Here's my wicked diagram...

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Old May 21, 2012 | 09:05 PM
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you want to hook it up to 87.

87a is constinte power from 30 then when you trigger 86 and 85 together. it trigger the arm from 87a to 87. then 87 will have the power
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Old May 21, 2012 | 09:09 PM
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hook 85 off the relay to com on the hobbs switch then 3 on hoobs switch to ground. then hook up 86 to a switch power. then hook 30 up to a fusable power. then hook up 87 to the pump
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Old May 21, 2012 | 09:11 PM
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Thanks a lot Matt! Where should I get the switch power for 86? Will the alternator be alright?
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Old May 21, 2012 | 09:14 PM
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yes that would work i would put a fuse inline. or you can do it any where you have a big enough power wire ( power distrobuter box)

Last edited by tt383lt1; May 21, 2012 at 09:19 PM.
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Old May 21, 2012 | 09:19 PM
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Sorry man, I have electrical down syndrome. What do you mean by that?
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Old May 21, 2012 | 09:22 PM
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they make a couple designs. ether one will work as long as you have the right fuse in it. and by distrobuter box. i mean
Attached Thumbnails Final question about relay/hobbs wiring-fuse.png  
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Last edited by tt383lt1; May 21, 2012 at 09:28 PM.
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Old May 21, 2012 | 09:25 PM
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Oh gotcha an inline fuse. Thanks a ton Matt! Good luck with the Camaro on Wednesday!
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Old May 21, 2012 | 09:45 PM
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2 last questions. Swear to God!

1. How big of fuses should I get for the battery and accessory wires? I have some 20 ampers laying around.

2. So the 5th prong marked 87Q is not used at all in this setup?
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Old May 21, 2012 | 10:19 PM
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From: mn
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no the 87a is not used on this setup and what pump are you running? it maters on the amprage it takes. on my dual a1000 setup i used 30 amps on both. if you have any more question i will be glad to help.

on a relay you always use the three prong 85, 86, 30

the other two are. (87) is a switched what ever 30 is hooked up to pos or neg. when triggered then no power/ ground when its not trigger( the way you have it)

and 87a is on it all the time then switched off when triggered (the way you dont have it)

Last edited by tt383lt1; May 21, 2012 at 10:38 PM.
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