One important thing to keep in mind is how fresh the batteries are. Power delivered to the ignitor is what causes the ignitor to fire. And power is voltage x current. Newer batteries will usually have a lower voltage drop when driving an ignitor and will then need less current to fire the ignitor. Best way to test is to use a constant current power supply to see what the no-fire and all fire limits are, and to monitor the voltage to make sure it is lower than what a typical launch system supplies.

The resistance of the launch system itself will also affect the all-fire and no-fire levels, typically raising the currents required.

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Tim Barr
NAR 51403 SR