Why is my StratoLogger firing ....

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Walldiver7

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Would anyone know why my StratoLogger is firing the drogue charge while on the table (horizontal)?

Details:
I'm powering this one with 3 lipo cells in series (400mah, Full charge is 12.something volts verified by beep-out.). The problem only occurs when the power has been left off for more than an hour and then, I return, to switch it on.. and it fires (every time). This does not occur upon connecting the charge and then cycling the switch. I have my switch in the supply line.

Am I missing something?
 
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Would suspect it's something in the startup logic--perhaps a function test that, with the marginally high voltage (it IS rated to only 12, yes?), causes the fire. Is it only with that power supply?


Later!

--Coop
 
Coop,

That's my next test; Put it back on the 9V and see what happens. I'm going to be disappointed if it does work with the 9 and not the 12v source. I needed the 12v for telemetry purposes. The stratologger is spec'ed from 4v to 16v.

There is one unknown here that I haven't accounted for. The lipo cells have a protection circuit on them. The have over-voltage/current protection as well as under-voltage protection too.
 
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There is one unknown here that I haven't accounted for. The lipo cells have a protection circuit on them. The have over-voltage/current protection as well as under-voltage protection too.

The Stratologger has a largish capacitor on the power supply that protects against momentary power loss during flight. It is possible that the inrush current to charge it is activating the protection circuits in the battery. This is easy to test. If the problem reliably occurs after you carefully discharge that capacitor and then apply power...
 
The Stratologger has a largish capacitor on the power supply that protects against momentary power loss during flight. It is possible that the inrush current to charge it is activating the protection circuits in the battery. This is easy to test. If the problem reliably occurs after you carefully discharge that capacitor and then apply power...

OK, so my battery shuts down during the charging of the cap. Would this cause the mc to trip the pryo circuit? I guess I'd better test that. Thanks for the tip, David!
 
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