Launch controller wiring help

Im building my first launch controller and found some great inspiration from this post that Green Jello started when he built his launch controller.
https://www.rocketryforum.com/showthread.php?46008-Designing-a-custom-launch-controller

Im planning on building the same controller but i have gotten stumped, by breadboard wiring almost work but not quite. since this is my first electronics project I'm now starting to question all my connections. So i need some help from one of you more experienced wiring guys telling me if I'm on the right track here and what i need to do to get it the way I want it to work.

here is what i want it to do:

1. on POWER yellow light indicating battery connection.
2. on inserting the SAFETY SWITCH the green continuty light lights up if there is continuty
3. on ARMING using the flip up arming switch that lights up red when engaged the beeper starts buzzing indicated the controller is armed
4. pushing the LAUNCH BUTTON the green continuty LED and the bussed goes out and the TO ROCKET led lights up brightly

All of what i have outlined above is happening except for the arming switch lighting up when engaged. If i reverse the power and ground the switch lights up but then the rest does not work.

Tell me what I'm not getting here...
Much appreciated

Leds only work in one direction try reversing the arming led

it sounds like your polarity to the arming switch is reversed, in the US ground is usually negative with positive being the 'hot' wire.
Rex

Hey guys thanks for the feedback!
Do you mean switching the "power" and the "ground" connections?
The switch has three connections power, acc & ground. I tried to switch the power and ground and that did not work...

How does the arm switch work? Is the ground and power pins open until the switch is moved? What about the acc pin. Is that switched also? If so what pins does it connect to and at what positions?

Does the power and ground supply voltage to light the LED and when the switch if flipped, the power is applied to the acc pin? If that's the case, the LED would be on as long as there is power and ground applied. I'm not sure you can make the switch work the way you want in that case.

This is the correct way to wire your circuit with the components chosen.
Steve G

Thanks for taking the time to put me on the right track everyone. And thanks for the wiring schematics sghioto, that was just what I needed. Everything works as I want, except...the buzzer do not go silent when I push the launch button. Is it supposed to with these schematics, or did mess it up?
Again thanks for taking the time educating a newbie on wiring.

I didn't see that in your first post. In that case just connect the negative side of the beeper to the negative side of the green LED.

Steve G

That did it! Thanks for your help on this!

All the best
Martin

I am building this controller for an external 12v battery. But when my son uses it for his LPR rockets that will not work.
Has anyone built a controller with an internal battery pack, and connections for hooking up an external battery? Then having a switch on the controller to switch between the different power sources? What kind of switch would I need?

Thoughts?

We use 12 volts for all our pads including the model rockets so you probably don't need to two batteries. If you do then get a SPDT (single pole double throw) switch with a center position OFF rated 20 amps at an auto supply store and connect the center tab to the safety switch and the outer tabs to the batteries as shown in this revised schematic. The center off position will disconnect both batteries when not in use.

Steve G

I assume your son can't use the external 12V because it's a "car" battery and too large or unsafe for him to be handling. If that's the case, you can get a smaller car starter that he should be able to handle and will work for all of your launches. I have this one LINK and use it for my controller, but have also used it to power the club's controllers a time or two. It has a USB port so you can charge phones, etc. also. I've also started several cars at launches that had let their batteries run down.

One tip, the power wires from your controller, make them different lengths by several inches. That way if you pull on them and drag the battery clamps together, they will be at different distances and won't short together.

That is a great suggestion! And you are right on about the car battery safety aspect for my sons.

I'm currently building away on this launcher. Will take me a while before it's going to get done, since there are a few competing projects at the time...

I'll post some pictures as I go.
Thanks everyone