What turns on a USB battery pack?

catmandu

catmandu

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Catmandu
So I am doing a semi-permanent installation of my Stratux in my RV. I am using this battery that has pass-through capability. But if I leave the battery pack plugged in always to the Stratux, I will start each flight with no battery backup, which is no bueno since I am using the Stratux AHRS and my iPad with WingX and synthetic vision as my tertiary backup for IFR.

What line in the USB cord from the battery to the Stratux do I need to switch (via my E BATT on-off toggle) to wake up and shut down the battery pack, as happens when you plug in and unplug the USB cord to the battery pack? My assumption is the red power line, like shown in this instructable, but, we all know what happens when you assume . . .
 
patillaje-conector-usb.jpg


Of course this assumes the manufacturer of the cable used standardized wire colors...
 
Thanks for that. I guess though my question is more related to the battery pack. Just not sure what it senses to switch it on. My simple mind says if it is current flow, then either +5v or ground could be switched. But if it is Data request or some such thing, I would suppose one of the other two lines would need to be switched. I guess I can try until it works, only four wires and I'll be hacking a cable anyway.

Edit: Never mind, after my twelfth cup of coffee I realized it must be the sensing of the resistance of the completed +5v circuit that turns it on, just like any other switch on a computer.

My parent's life savings for my engineering degree, and look at me now. :oops:

Off to the hangar to hack a wire.
 
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catmandu said:
So I am doing a semi-permanent installation of my Stratux in my RV. I am using this battery that has pass-through capability. But if I leave the battery pack plugged in always to the Stratux, I will start each flight with no battery backup, which is no bueno since I am using the Stratux AHRS and my iPad with WingX and synthetic vision as my tertiary backup for IFR.

What line in the USB cord from the battery to the Stratux do I need to switch (via my E BATT on-off toggle) to wake up and shut down the battery pack, as happens when you plug in and unplug the USB cord to the battery pack? My assumption is the red power line, like shown in this instructable, but, we all know what happens when you assume . . .
Click to expand...

FYI, that battery pack is garbage. I bought it to run my Stratux, was very, very disappointed with it. It'll only run a Stratux for about 2 hours, and mine stopped holding a charge about about 3 months. Company did replace it for free, but I'd get a better battery pack from Anker.
 
bradg33 said:
FYI, that battery pack is garbage. I bought it to run my Stratux, was very, very disappointed with it. It'll only run a Stratux for about 2 hours, and mine stopped holding a charge about about 3 months. Company did replace it for free, but I'd get a better battery pack from Anker.
Click to expand...
Well, I think for his use case, the battery clock only starts ticking if he loses his electrical in the plane. The pack will be charging when the airplane is running and pass-through running the stratux.
 
exncsurfer said:
Well, I think for his use case, the battery clock only starts ticking if he loses his electrical in the plane. The pack will be charging when the airplane is running and pass-through running the stratux.
Click to expand...

Given my experience, I'm not sure I'd trust it. YMMV.
 
I did some testing with a stripped open cable. A switch on the +5v line does in fact turn the battery pack on and off.

I initially looked at those in line switches, but my panel just got cleaned up and simplified. I installed DPST locking toggles for all the critical circuits (which only need SPST), just because I found a deal on a lot of 6 NOS on eBay. Using the available circuit on the E BATT toggle keeps my panel tidy, and uses an existing checklist item to transparently turn on and off the Stratux at an appropriate time.

Primary power for the Stratux via the pass through battery is from a 12v to 5v power supply wired into the Main Buss. But thanks for the feedback on the battery, I'll operationally test running on battery power alone for 30 minutes or so at the end of some VFR flights. As I said, it is for tertiary IFR attitude info, all I want is 30 minutes max to get out of the clouds if my primary and secondary electrical supply to my primary and secondary attitude indicators get nuked by a single unforeseen event (which I really don't expect, but then again, nobody ever does).
 
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I have a variety of battery packs for my Stratux. Most supply power on plug in. One does nothing until an "on" switch on the case is depressed.
 
Thanks. I hacked a cord and had some success getting what I wanted, but not reliably. I suspect dealing with the 28 ga wire has something to do with it, so I got a cord from monoprice that uses 24 ga wire for power and ground, hopefully that will work better for crimping connections.
 
The 24 ga wire is doing things better, although as soon as I go to 'pass through' mode I lose the red LED on the RPi3. Stratux still seems to work properly, though, so I am just going to roll with it for a while. I need to go test the intended purpose at some point (fly for a bit, then take away 12v power and make sure I get 30 minutes of attitude information).
 
I like pictures of switches and wiring and stuff. Can you accommodate? :)
 
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