Anyone have experience running a Vertex Mag with a painless shut down relay?I have a kill switch in the dash . It works fine, but the shut down relay will not kill the engine when the master disconnect switch is flipped.I have the kill wire comming from the shutdown relay connected on the dash mounted kill switch. The problem is that with the dash toggle switch in the run position ,the master disconnect will not ground the Mag. Any ideas are welcomed! Thanks
Can you install an additional 5 pin relay at the cutoff switch? 85 - 12v from the switched side of the cut off 86 - Ground 87- Not used 87A - Ground 30 - Kill lead on the mag.
You are making this to complicated. I run a Vertex mag with an internal coil. I just run a wire from the external post to a switch to ground. Open the switch to run, close the switch to ground to kill the engine.
He does have a shutdown switch on the dash to shutoff the mag. He wants to be able to shut down the mag when the power disconnect switch it turned off.. thus the relay.
Thanks for the response. The relay (painless) is wired as follows, 85 ground 86 12v from master shut off, 87 not used, 87a to ground, 30 to mag kill sw. to mag, toggle sw. to ground . Using a 12v test light(clipped to+ battery and probing the 30 wire the relay works by switching the master sw. on a nd off (on=light out , off = light on). but when the 3 wire is then hooked to the Mag the test light stays on, with no effect from the master switch!
I ran that set up on the car in my avitar when it had a battery. I may not be folowing exactly, but I am thinking you need to seperate your toggle kill and the kill from the relay. Two seperate circuts. Mine worked beautifully.
I think you have the relay wired right, but if the motor keeps running you may have the relay contacts wired in series with your kill switch instead of parallel. it should be: Mag kill wire to 30 and kill switch, then other side of kill switch to ground and 87a to ground. EDIT: Also, what you are seeing using your test light like that, (if I understand what you're saying) is continuity through your kill switch. Try it with it off. http://www.the12volt.com/relays/relays.asp
Problem solved. It was alternator feedback. Installed a 4 post disconnect, to separate the alternator feed wire from the pos. cable(to the starter) in the Off position. Thanks for your replys!
Doh! I hadn't thought of that. In fact, I'm not sure I understand why it works that way? When you ground the mag, you give the current an easier path than going through the coil part of the mag. I've always thought of the mag as a totally separate system. Even a positive ground shouldn't do that? Hmmm.... Oh well, glad you're running and stopping anyway.
Hey pro 39, I PMed GMC Bubba and he jogged my memory a bit. The alternator was holding in your relay, not powering your mag like I was thinking. He also reminded me that your relay will drain your battery if you leave the switch on. I'll see if I can find a better circuit to prevent the battery drain without having to hit the switch each time.
If you add one relay and move your kill switch, the relays won't drain the battery if you leave the master switch on. Here's my schematic and ladder logic: The relays do not energize until you hit the start switch. The hold relay keeps the kill relay powered until you hit the kill switch. The kill switch also resets the circuit to a no power drain condition. Your kill switch works backwards in this circuit: Close to run, open to kill. Your battery can still drain if kill switch is set to run but the engine failed to start or has stalled.
That is because the relay takes power to work. A relay is just a set of contacts that are engauged by magnetic coils. I would dump the relay all together and just run a switch that goes to ground when it is closed and not grounded when it is open.
I believe the problem is that some drag racing classes require a battery cut off at the rear of the car that also kills the engine. That is why the relay is needed.
The relay cannot work if you cut the power to it. On a mag equiped car cutting power will not kill the engine because it makes its own power, if you need an external kill switch then the kill switch would need to go to the grounding post of the magneto and to ground on the switched end.
Golly, that's a little over my head. But if they only allow you to have one switch at the back of the car, how are you gonna kill the engine and the battery power at the same time if you don't use a relay?
Pro, Will this work for you? - http://www.flamingriver.com/index.php/products/c0015/s0002/FR1010 Terry
Benno, I think he NEEDS the master power switch at the back to kill the engine. That alternator feedback is a common problem, mag or otherwise. You can also solve the problem by running the alt. charge wire all the way back to the battery side of the master switch (as long as it's not teed into any other circuit)
This kit uses a normally open relay. When the power is shut off it closes the relay sending the mag to ground to kill it. I had to use one when I installed a battery so you could kill the power and the mag at the same time. And it sounds like he got it solved.
Oops! I just realized my drawings in post #12 were probably much more complicated than necessary. That is how I would wire a race car that used a start push-button on the dash. If you are using a normal keyed ignition switch just power the kill relay with the old ignition circuit. No need for that holding relay, your battery won't drain because you're not getting relay power directly from the battery, and you already solved the feedback problem. Also, you can add all the extra kill switches you need as long as they are wired in parallel with the nc contact. Should work great. Sorry for the extra confusion.
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