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primetime347
08-27-2016, 09:02 AM
I am looking to step up to the big leagues with purchasing a COBRA firing system. But I am confused about this one thing. And I apologize if this is a self explanatory question/answer. I just have no idea what this means.

When looking at different power options for the 18M, "Using 9V batteries, you can fire a maximum of 10 e-matches in series, or 4 e-matches / Talon Igniter Clips in parallel."

WHAT IN THE WORLD DOES THAT MEAN? Can someone break that down Barney style for me? Will 3 9v batteries or using the 14.8v LIPO battery pack fire off all 18 ques with Talon igniters?

I will only be using Talon igniters since I have yet to apply for my Type 54.

Thank you for all of your help!

cmalloy513
08-27-2016, 10:03 AM
10 ematches in series or 4 ematches/igniters in parallel refers to the way you wire you ematches/igniters PER CUE. This is if you want to wire multiple multiple ematches/igniters in one cue. In my show this year I had several cues wth 4 igniters per cue using the 9V batteries. So yes, the 9V batteries will fire all 18 ques probably for 2-3 shows. You could go with the LIPO but I don't think it's needed for what your doing.

primetime347
08-27-2016, 08:31 PM
10 ematches in series or 4 ematches/igniters in parallel refers to the way you wire you ematches/igniters PER CUE. This is if you want to wire multiple multiple ematches/igniters in one cue. In my show this year I had several cues wth 4 igniters per cue using the 9V batteries. So yes, the 9V batteries will fire all 18 ques probably for 2-3 shows. You could go with the LIPO but I don't think it's needed for what your doing.

Thank you so much cmalloy! This makes total sense now! I never even thought of running more than one igniter off of one que at a time. I appreciate the help!

basicbosch
06-07-2020, 11:13 PM
Ok so if anyone can answer I have a 46M and I am wondering what is the max amount or MJG you can use in parellel and how many in series from each cue. Mine has the lipo battery. Also I see on the Cobra page that they "offer" a 24volt upgrade but I am completely unaware how to do that

basicbosch
06-08-2020, 12:02 AM
I meant to say 36M

Robbro097
06-08-2020, 12:49 AM
For the 24 volt external power youd just hook 2 12v batteries together i do series (1 pos 1 neg terminal wired together) leaving 1 neg 1 pos free then run wire from those terminals to pos neg post on cobra mod 4995

Rick_In_Tampa
06-09-2020, 05:47 AM
Is this what you're saying? (Sorry... I like pictures)

4997

Robbro097
06-09-2020, 11:15 AM
Thats it rick, i even talked to cobra and they say i can use the deep cycle batteries from my boat but i picked up a cpl lawn tractor batteries there so much lighter lol

IndianaPH
06-09-2020, 08:36 PM
Is this what you're saying? (Sorry... I like pictures)

4997

Rick, I like pictures as well. Here is the 24V setup that I am using. I put two Weize 12V 12AH Sealed Lead Acid (SLA) AGM Deep Cycle Rechargeable Batteries (https://www.amazon.com/gp/product/B07QPYFBW6/ref=ppx_yo_dt_b_asin_title_o03_s00?ie=UTF8&psc=1) in a Seahorse 300 Case (https://www.amazon.com/gp/product/B001A1PT9A/ref=ppx_yo_dt_b_asin_title_o02_s00?ie=UTF8&psc=1). I also added a fuse between the batteries. I keep the fuse out until I have the leads hooked up to the module to prevent a short if the ends of the leads were to contact each other while I am hooking it up. If I forget to pull the fuse, hopefully the fuse will blow before I damage anything.

4999

I needed to add the external power as I realized I was stretching the limits of the LiPo in the 36M when I was testing using one cue to fire 5 e-matches simultaneously across 5 36S series slats (one e-match per slat). The issue I was having was the total distance I had using 15M (50') cables (heavy duty CEN50 from Cobra) between slats (approximately 200' between the first and last slat). I discussed the scenario with Zach at Cobra and he ran the numbers for me to confirm I was pushing the limits of the LiPo and an external 24V power supply would probably fix the issue. I built the above setup and then did a full scale test of my script with the external 24V power attached. My script is a little over 16 minutes and this setup allowed me to fire 105 e-matches, over 33 cues, across the five slats throughout the script. I am firing from one to five e-matches in series on each cue, with the majority of the cues firing three or four e-matches. I only had one e-match not fire, but the issue was traced back to a mistake I made when wiring, not a lack of power. Here is a picture of the setup while I was testing it.

5000

If you add an external power source, you need to confirm that the module is set to the correct voltage. From Cobra's website:

Toggle the voltage mode by pressing TEST and CH+ or TEST and CH- until the desired voltage mode is assigned. Power the module off and back on. The module will retain the voltage mode selected even if the unit is powered off or the batteries are removed.

IndianaPH
06-09-2020, 08:45 PM
I am looking to step up to the big leagues with purchasing a COBRA firing system. But I am confused about this one thing. And I apologize if this is a self explanatory question/answer. I just have no idea what this means.

When looking at different power options for the 18M, "Using 9V batteries, you can fire a maximum of 10 e-matches in series, or 4 e-matches / Talon Igniter Clips in parallel."

WHAT IN THE WORLD DOES THAT MEAN? Can someone break that down Barney style for me? Will 3 9v batteries or using the 14.8v LIPO battery pack fire off all 18 ques with Talon igniters?

I will only be using Talon igniters since I have yet to apply for my Type 54.

Thank you for all of your help!

primetime347, this might be informative.


https://www.youtube.com/watch?v=eCsZi8Oeey4

If you don't want to use talons, you can get MJG Igniters without a license. Here is a link: MJG Igniters from Cobra (https://www.cobrafiringsystems.com/mjg_igniters.html)

basicbosch
06-09-2020, 11:51 PM
Ok so with the system I have what is the max MJG I can fire off in series or parallel from the same cue

IndianaPH
06-10-2020, 12:40 AM
basicbosch, there are a lot of factors that go into the exact calculations, but for a quick answer, look about halfway down this page: # of Igniters by Power Source (https://help.cobrafiringsystems.com/support/solutions/articles/44001380462-continuity-clarified)

I believe that those numbers are best case scenarios and are for connecting the igniter directly to the module. If you need to add scab wire or are using long cables and slats, the numbers go down due to the added resistance. I believe Cobra is working on an easy to use calculator, but until they release it, you can contact them and they will help with determining the total numbers based on your conditions and wire lengths.

basicbosch
06-13-2020, 11:12 AM
Thank you that helps a ton.