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  #11  
Old 09-28-2015, 05:55 PM
UlteriorModem UlteriorModem is offline
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I just like the convienence of not having to lug around a brick with me also no hookup wires to fuss with.

A hot lipo can probably out perform a gel cell in supplying large amounts of current in a very short time span. Probably live to do 'dozens' of launches too.

One thing did concern me was dropping in what amounts to a dead short (the first few microseconds) onto a Lipo. I have seen the results of shorting out a lipo albeit a lot longer than microseconds. They will go off like a road flare!

Speaking of lipo safety I might see if I cant get some of that foamy tape over the battery springs just so they wont puncture one by accident. Punctures... see above sentence

Oh one last thing I will probably look into the JST connector and its conductors as to their ampacity. A mod may be in order
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  #12  
Old 09-28-2015, 06:19 PM
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BEC BEC is offline
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The PSII controller has a bright LED that lights if there is continuity after the key is inserted. See the spot between the two rocker switches (yellow and red). Then, when the yellow one is pressed a piezo beeper of some kind sounds a continuous tone. The two of them together draw a low enough current (I don't recall what I measured exactly) that the controller is Q2G2 safe.

The time it takes to fire a standard Estes igniter with the LiPoly is very short. I know I kind of chided the folks at Estes about the choice of that little orange JST connector as I found them to be lousy in small electric airplanes when the current draw was any more than about 2A (say a GWS IPS drive). But again the time is so short that in practice it's OK. (that's why you can see that there is a mini-Deans plug on the battery and I made a small mini-Deans to JST adapter to put the battery in the controller. I use the mini-Deans plugs on my small electric planes up to about 12A or so.

Point taken about protecting the sides of the pack from the springs. Certainly a pack that doesn't have a good heat shrink tubing wrap around it would benefit from some other protection there.
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  #13  
Old 09-29-2015, 02:50 PM
UlteriorModem UlteriorModem is offline
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When mine arrives I will most likely do some mods and check out the circuitry inside. Hrm maybe I should have ordered two

Anyhow I will report back in this thread on my findings.
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  #14  
Old 09-29-2015, 02:55 PM
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LeeR LeeR is offline
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If you never plan to use C cells, maybe just cut off the protruding ends of the battery springs? That way there is no potential for puncturing the LiPos.
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  #15  
Old 09-29-2015, 04:28 PM
UlteriorModem UlteriorModem is offline
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I thought about that and thought that maybe the cut off springs would leave sharp pointy ends and may be worse than before.

Is the unit 'welded' shut? I wonder.
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  #16  
Old 09-29-2015, 06:04 PM
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LeeR LeeR is offline
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One option would be to coat the covered ends of clipped battery springs. Globs of silicon caulk or globs from a hot glue gun.

It looks from the pictures that there are 4 screws for holding the case together, but look like "tamper-proof" types. I tend to find those to be more "tamper-resistant", and can be backed out with the right tool.

Have fun tearing it apart to see what makes it tick.

Finally, I found no explanation on any of the pages about this controller -- why does it look to have two sets of igniter leads? Or maybe the picture was misleading, does it have 3 clips on the positive, and a single clip on the negative, for clusters?
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  #17  
Old 09-29-2015, 08:16 PM
UlteriorModem UlteriorModem is offline
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Its just two sets of clips in parallel. Supposedly to ignite clusters of two I guess.

Dunno what you do if you have three let alone the 'extra' pair of clips dangling around. Probably cover that in the instructions but I don't have them yet...

ps; I poked around estes web site and they don't have the instructions online (yet) either.
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  #18  
Old 09-29-2015, 10:56 PM
Rex R Rex R is offline
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I should think that a couple of rectangular pieces of 1/32" ply would suffice to protect your packs.
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  #19  
Old 09-30-2015, 08:13 AM
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Shreadvector Shreadvector is offline
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Quote:
Originally Posted by LeeR
One option would be to coat the covered ends of clipped battery springs. Globs of silicon caulk or globs from a hot glue gun.

It looks from the pictures that there are 4 screws for holding the case together, but look like "tamper-proof" types. I tend to find those to be more "tamper-resistant", and can be backed out with the right tool.

Have fun tearing it apart to see what makes it tick.

Finally, I found no explanation on any of the pages about this controller -- why does it look to have two sets of igniter leads? Or maybe the picture was misleading, does it have 3 clips on the positive, and a single clip on the negative, for clusters?



The instructions (which do not download properly for me from the Estes website, but I have a printed copy at home that came with the controller) show you how to use the twin set of clips for one to 4 motor ignition.
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  #20  
Old 09-30-2015, 02:41 PM
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LeeR LeeR is offline
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Quote:
Originally Posted by Rex R
I should think that a couple of rectangular pieces of 1/32" ply would suffice to protect your packs.
Rex

Good idea -- and probably the simplest solution for protection. Would still allow for use of C cells with removal of the ply strips. I think I'd do a hybrid -- shorten the clips and epoxy the ply strips in, giving a little more room for the LiPos.

Have we sufficiently beat this almost-dead horse?
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