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Safe current levels for Q2G2's??

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luke strawwalker

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Anybody know how much current a Q2G2 ignitor can pass without firing?? I just reworked my Estes Solar Controller and Pola-Pulse to use LED indicators with internal resistors and wanted to make sure they're safe for the Q2G2's...

I REALLY like the looks of these ignitors, and I'm looking forward to using them!

First I want to run an amp test on my launchers though to make sure I don't need higher resistance on the continuity indicators though... :)

TIA! OL JR :)
 

DaveCombs

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Shred posted some basic info here, but as yet there's nothing official posted from Quest.
 

Micromeister

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Luke:
I just changed all 3 of Narhams launch contol systems to a high brightness 8000mcd green LED's with a 680 ohm resistor continuity lamp that limits the current to 20mA which seems to have solved the problem.
hope this helps
 

falingtrea

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As Bob Krech pointed out in the thread referenced previously, Quest does have info posted on the website here. The Basic fire current is 120mA so any design using an LED limited to 20mA should be safe.
 

shreadvector

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There is an "all fire" current where every igniter will fire and there is a "no fire" current level where zero of the igntiers will fire. Once you know these you can design or select a launch controller that works with your igniters.

The Quest electronic controllers are extremely safe for these (and other ) igniters as the electronic continuity circuit only passes a very low current. Much discussion here:
http://www.rocketryforum.com/showthread.php?t=326&highlight=q2g2

http://www.rocketryforum.com/archive/index.php?t-326.html
 
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luke strawwalker

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Luke:
I just changed all 3 of Narhams launch contol systems to a high brightness 8000mcd green LED's with a 680 ohm resistor continuity lamp that limits the current to 20mA which seems to have solved the problem.
hope this helps
Thanks Micro...

I just rebuilt both my 'vintage' Estes controllers again... I had switched them over 20 years ago to LED's and resistors I scavenged from an old VCR and soldered in to replace those stinking little six volt flashlite bulbs that they came with, and I added a 'battery continuity' indicator circuit since I switched them over to external clips for 12V car batteries at the same time.

I was looking at the controllers here while back (an old gray Solar Controller and a Pola-Pulse whose intended battery always sucked) and while I'd used pretty good lamp cord for the battery wires and HD charger style clips, I wanted to upgrade them from the dinky spare parts LED's and desoldered/resoldered resistors and soldered bridge wires connecting everything up in the case. I found those little 'LED indicator' lites at RS with the resistors built in and simply rewired everything and resoldered and tidied up the things a bit, drilled holes and installed the indicators, which work beautifully. I also replaced the thin leads to the pad with lamp cord and put a female plug about a foot outside the case, for using regular 25 foot extension cords for the launch leads, and made a male plug 'clip whip' which then connects the extension cord to the ignitor. I've tested it with Estes ignitors and it works beautifully, but as I was discussing at our club meeting last night, I don't want to burn a Q2G2 testing the system when I can plug a multimeter in instead.... and then CAREFULLY make the first launch... :)

THanks again! OL JR :)
 
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