Clip whips and multiple-motor continuity testing

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The main problem I have with the “measured resistance in series” solution is that it both limits me to specific igniters (or whatever you want to call them), and requires me to trust that they always have the same resistance regardless of manufacturing and environmental conditions. I don’t like to design things where I have to trust someone else got their end right. I *could* literally check the resistance of every igniter I use... but that’s too much work, and what if I forget the meter? No thanks.
Electric matches are used by the thousands in fireworks shows and often in series with other ematches.
But still, if it’s too much work to measure the resistance of ematches for a little piece of mind, there’s probably nothing any of us can say. I would do a bunch of them at a time at home and set them aside in groups. Then just grab a group large enough to support the cluster you have planned. Then it doesn’t matter if you forget your meter. Also, using checklists can help you not forget things like meters.
 
I am the OP :D
My launch controller - which I had no issues building - fits my needs but lacks the ability to distinguish between valid continuity on only one igniter versus all igniters. There are multiple ways to solve this problem and most of the have been mentioned here. It would be convenient if I could find a low-effort solution using my existing setup.
If you can check continuity at the pad, check each starter *then* twist them together. Again, except for e-matches, I wire all other starters in parallel.
 
I am the OP :D

Continuity means no more and no less than having a good electrical circuit with the igniter - it can pass current.

The issue on clusters comes from having multiple igniters and trying to confirm *all* of them have a good electrical connection.

My launch controller - which I had no issues building - fits my needs but lacks the ability to distinguish between valid continuity on only one igniter versus all igniters. There are multiple ways to solve this problem and most of the have been mentioned here. It would be convenient if I could find a low-effort solution using my existing setup.
Not a good electrical circuit but whether you have continuity. no shorts or open, so you verified what I stated If it was good indicator it would be fool-proof. Again your initial remedy...of multiple LEDs with rotary works but is a pain to modify and implement. While I am not a complete fan of in series, that allows 1 LED to do the Job. I still worried about 1 motor igniting first and nichrome burns open, yielding one ignition.
 
Starters have higher current needs than electric matches, usually by a large factor. Placing multiple starters in parallel without selecting starters that match pretty closely, will result in the starter with the lowest resistance receiving more current (google current divider circuit). That igniter will light first. Equally important is the fact that your controller must provide the sum of all currents needed to quickly ignite the starters, so if you’re trying to light three starters that require 6 amps each to quickly light you must source 18 amps. If that causes your voltage to sag you may have a problem.
In a series circuit you have similar problems. Electric matches do not give off as much heat as starters but they require much less current. You make up the difference with some kind of pyrogen. They can be connected in either series or parallel and quality ones will light quickly.
Either way you really want to match them for resistance.
The other way to do this is one I mentioned much earlier. Use a controller that has a drag race configuration and connect each starter to a different set of pad wires. Most multipad systems will do that easily and report continuity for each starter while doing it.
 
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