NX SPDT relay / wiring ?
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NX SPDT relay / wiring ? I didn't get the wiring harness with my NX relay, so after a phone call to Nitro Dave's this AM I thought I'd post the pinout :
86 : +12v keyed ignition (low amperage side), wot switch and manual activation switch in line
30 : +12V to battery (high amperage side)
87 : + to noids
85 : to ground (via FPSS and window switch)
Originally they told me that 87a went to +12v battery, from my research that is incorrect.
http://www.the12volt.com/relays/relays.asp
According to that document, battery +12v should be on post 30, live to 87A until 85 and 86 connect, then 30 connects to 87 which becomes +12v.
The long and short of this is this :
I have stereo +12v connected to 86, via manual and WOT switch.
I currently have 30 connected to +12v battery.
87 is + to noids, and 85 is ground via FPSS and window switch.
I am popping the 15amp stereo fuse in the driver door fuse panel when the system activates, which would lead me to believe that the stereo +12 side is grounding when the relay activates.
Anyone know WTF ?
Rob (Bad30th)
86 : +12v keyed ignition (low amperage side), wot switch and manual activation switch in line
30 : +12V to battery (high amperage side)
87 : + to noids
85 : to ground (via FPSS and window switch)
Originally they told me that 87a went to +12v battery, from my research that is incorrect.
http://www.the12volt.com/relays/relays.asp
According to that document, battery +12v should be on post 30, live to 87A until 85 and 86 connect, then 30 connects to 87 which becomes +12v.
The long and short of this is this :
I have stereo +12v connected to 86, via manual and WOT switch.
I currently have 30 connected to +12v battery.
87 is + to noids, and 85 is ground via FPSS and window switch.
I am popping the 15amp stereo fuse in the driver door fuse panel when the system activates, which would lead me to believe that the stereo +12 side is grounding when the relay activates.
Anyone know WTF ?
Rob (Bad30th)
Last edited by Bad30th; Mar 29, 2004 at 03:34 PM.
85 and 86 should be used for the low current side. Just put everything (12V ignition/WOT/window switch/master arm) in series with 85 and ground 86. 30 and 87 are the high current poles so run 12V direct from battery into 30 and noids+ to 87 and noids - to ground. If it's a SPST relay it won't have an 87a terminal. In the case of a SPDT relay 87a is just not used in a nitrous application. 87a would be used for something like low/high beams. If power came in on 30 it would go to 87a which would provide power to the low beams until you hit the high beam switch completing the 85 to 86 circuit, then power would be diverted to 87 which would power the high beams.
HTH
HTH
PS: I believe you can switch 85 and 86 and 30 and 87. IE: it does not matter which one is power and which is ground.
If everything is hooked up right (IE noids are not on the low current side of the relay) you might have a short somewhere in your switches. What do you mean by you have manual and WOT switches?
This may help:
If everything is hooked up right (IE noids are not on the low current side of the relay) you might have a short somewhere in your switches. What do you mean by you have manual and WOT switches?
This may help:
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Thanks for the help, I was correct and had hoped I wasn't going nuts... 
I will unplug the 30 and 87 and see if I can get the relay to click with just 85 and 86 wired, and take it from there.
(Oh, and I meant I have a microswitch for WOT on the throttle mechanism and a manual switch in the ashtray to activate they system).
One last question - if the circuit between 85 and 86 completes, does it not send the +12v from 85 to 86 ground ? Or does the coil prevent 86 from grounding (and thereby popping the fuse ?).
When I originally hooked up the relay I had a ground on 87a and popped a big stereo fuse when I connected 30 to +12v battery and 87a was grounded, heh. Think I screwed up the relay ?
Thanks for the help, you guys rock.
Rob (Bad30th)
I will unplug the 30 and 87 and see if I can get the relay to click with just 85 and 86 wired, and take it from there.
(Oh, and I meant I have a microswitch for WOT on the throttle mechanism and a manual switch in the ashtray to activate they system).
One last question - if the circuit between 85 and 86 completes, does it not send the +12v from 85 to 86 ground ? Or does the coil prevent 86 from grounding (and thereby popping the fuse ?).
When I originally hooked up the relay I had a ground on 87a and popped a big stereo fuse when I connected 30 to +12v battery and 87a was grounded, heh. Think I screwed up the relay ?
Thanks for the help, you guys rock.
Rob (Bad30th)
Last edited by Bad30th; Mar 29, 2004 at 03:11 PM.
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Alright, some quick lunchtime work in the parking lot has revealed these test results :
1) disconnected all connections from relay. replaced stereo fuse. +12v switched was on 86, FPSS/window/ground via 85.
2) attached +12v switched to 85 and ran a ground to 86 (reversed them), ignition on, armed manual switch. Relay started clicking on/off with WOT switch. Good !
3) Put +12v battery connection on 30. Test with voltmeter and get +12.05v between 30 and 87a. Good. 0v between 30 and 87. Good. Stereo fuse still intact. Good.
Here's "teh suck" part.
4) Arm system via manual ashtray switch, and was going to test for 12v on 87 when relay opened. When WOT switch was depressed it blew the stereo fuse. (I have the low amperage +12v side running off the fused/ignition stereo +12v line).
I'm thinking the damn relay is not working right, suggestions ?
Rob (Bad30th)
1) disconnected all connections from relay. replaced stereo fuse. +12v switched was on 86, FPSS/window/ground via 85.
2) attached +12v switched to 85 and ran a ground to 86 (reversed them), ignition on, armed manual switch. Relay started clicking on/off with WOT switch. Good !
3) Put +12v battery connection on 30. Test with voltmeter and get +12.05v between 30 and 87a. Good. 0v between 30 and 87. Good. Stereo fuse still intact. Good.
Here's "teh suck" part.
4) Arm system via manual ashtray switch, and was going to test for 12v on 87 when relay opened. When WOT switch was depressed it blew the stereo fuse. (I have the low amperage +12v side running off the fused/ignition stereo +12v line).
I'm thinking the damn relay is not working right, suggestions ?
Rob (Bad30th)
Last edited by Bad30th; Mar 29, 2004 at 03:39 PM.
well if you don't have a window switch or something else in line to cut down the current on the low current side it may be drawing too much although I thought the relay should take care of that. Try putting a test light bulb in line with everything on the low current side to raise the resistance. Shouldn't be necessary but worth a shot because everything else sounds kosher.
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I got things straightened out I think... Will road test tomorrow.
I remembered I had an extra relay for the bottle heater to test with (turns out the relay is OK I think), and I picked up some 15amp fuses on the way home.
Pulled off all the connections from the relay. Connected up just a ground to 86 and +12v switched to 85. Double-checked connections on the manual ashtray switch and WOT switch. Ignition on, ashtray switch armed. Closing WOT switch makes relay click. Good.
Added +12v battery connection to relay 30. Checked with voltmeter, 12v from post 30 to ground. Good. 12v from 87a to ground. Good. 0 volts from 87 to ground. Good. Stereo fuse still not blown. Very good !
Crossed my fingers and activated the WOT switch - the relay clicked and the fuse didn't blow, with 12v on 87 ! :woot:
OK. This means as long as my window switch and FPSS work (remember I tested the relay with just a ground) things should be straight and I should be rocking. I'll know after a quick road test tomorrow AM !
Thanks for your help 5 Liter Eater,
Rob (Bad30th)
I remembered I had an extra relay for the bottle heater to test with (turns out the relay is OK I think), and I picked up some 15amp fuses on the way home.
Pulled off all the connections from the relay. Connected up just a ground to 86 and +12v switched to 85. Double-checked connections on the manual ashtray switch and WOT switch. Ignition on, ashtray switch armed. Closing WOT switch makes relay click. Good.
Added +12v battery connection to relay 30. Checked with voltmeter, 12v from post 30 to ground. Good. 12v from 87a to ground. Good. 0 volts from 87 to ground. Good. Stereo fuse still not blown. Very good !
Crossed my fingers and activated the WOT switch - the relay clicked and the fuse didn't blow, with 12v on 87 ! :woot:
OK. This means as long as my window switch and FPSS work (remember I tested the relay with just a ground) things should be straight and I should be rocking. I'll know after a quick road test tomorrow AM !
Thanks for your help 5 Liter Eater,
Rob (Bad30th)
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So it looks like the relay is good. If tomorrow blows another fues you'll have to check your wiring on the arming switch and WOT switch. Nothing should go to ground on the low current side of the relay other than the ground for the window switch and any LED/lights you have. Everything should be in series. 12V --> arm switch --> WOT switch --> relay 85; Then 86 --> switched ground from window switch (yellow on an MSD and white on a Harlan switch).
It seems really simple but I have been meeting with my own challenges with the lighted master arm switch and LED I'm adding to tell me when the noids should be spraying. Haven't blown a fuse or fried anything yet though.
It seems really simple but I have been meeting with my own challenges with the lighted master arm switch and LED I'm adding to tell me when the noids should be spraying. Haven't blown a fuse or fried anything yet though.
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breaking the Nittos loose at 40mph ! 
Popped in the 100 shot jets this morning and took her for a spin - it's definately working now !
Funny thing is I don't think I changed anything really, just double-checked all the wiring.
Thanks again for the sanity check !
Rob (Bad30th)
