My 3 launch circuit controller

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gwh

Well-Known Member
Joined
Nov 24, 2016
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Location
Kamloops, BC
I built a 3 circuit launch controller to ensure ignition of a 3 engine Falcon Heavy model.

I wanted to be able to check continuity of each ignitor independently, and also control whether each igniter circuit is activated.

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This box is the result. A 12V battery provides the juice when needed. Passing power through each indicator LED limits circuit current to a level where there isn't enough power to fire a typical ignitor. When its go time a safety key enabled launch button sends power to 3 individual relays to switch power from the LEDs to a low impedance circuit so the ignitors see close to full battery output. In total I run 3 positive wires to the pad and one ground return. At the pad I need to check for visual signs of a short, if not I can assume that an indicator light means the igniter circuit is fully continuous at each engine.

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With this I can do one 3 engine launch, or 3 individual single engine launches at whichever tempo I choose. The system is also upgradable to handle 6 engine ignition or 3 pairs of 2 engines since each relay has terminals for 2 circuits and I installed enough terminal blocks to do so.

20200221_222346.jpg

I moved the launch button off the main box onto a remote switch to move further away from the pad. Its a toss up as to whether I would have been better to build this all at the pad and not a remote box or have it partially away for safe(r) testing of circuits. All that copper wiring wasn't free.

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Last edited:
Nice use of industrial Terminal blocks. Those are great.
 
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