Sailplane Power Supply

On Friday, January 27, 2017 at 11:35:50 AM UTC-7, Andrey Lebedev wrote:
Hello group,

I did a wiring overhaul in my cockpit recently. I learned a lot in the process and decided to document my research for various ways you can connect batteries to your electronics. Hopefully this will be helpful to folks like me half a year ago.

https://medium.com/taming-a-sailplan...y-479b6632fedd

For my ship I've chosen scheme I call "Commuted circuits". I must admit I was pretty amazed by elegance of the solution.

Any feedback, especially practical experience, is highly appreciated.

--
Andrey Lebedev
WU

I like the redundancy of combining two batteries with individual DPDT switches. Flipping a battery selector, creates a power glitch which shuts down my computer and invalidates the trace. The Ideal diodes sound like the way to go with this arrangement. I found this (unpopulated) Ideal diode circuit board online; with parts from Mouser each board would run about $2 each.

https://github.com/xioTechnologies/Ideal-Diode

On Monday, January 30, 2017 at 8:43:45 AM UTC-5, wrote:
On Friday, January 27, 2017 at 11:35:50 AM UTC-7, Andrey Lebedev wrote:
Hello group,

I did a wiring overhaul in my cockpit recently. I learned a lot in the process and decided to document my research for various ways you can connect batteries to your electronics. Hopefully this will be helpful to folks like me half a year ago.

https://medium.com/taming-a-sailplan...y-479b6632fedd

For my ship I've chosen scheme I call "Commuted circuits". I must admit I was pretty amazed by elegance of the solution.

Any feedback, especially practical experience, is highly appreciated.

--
Andrey Lebedev
WU

I like the redundancy of combining two batteries with individual DPDT switches. Flipping a battery selector, creates a power glitch which shuts down my computer and invalidates the trace. The Ideal diodes sound like the way to go with this arrangement. I found this (unpopulated) Ideal diode circuit board online; with parts from Mouser each board would run about $2 each.

https://github.com/xioTechnologies/Ideal-Diode

I have used the individual switches for each battery going to the main bus for over 20 years with no negative issues. When it is time to switch I turn the new one on and then the old off. The current flow that may occur for a couple seconds, given that the voltage differential is less than 2 volts, has never caused me any problems.
I use spade connectors at the bus and have never had one loosen. It no doubt has saved a number of dropped screws into the bottom over the years. We don't have much vibration to worry about, compared to airplanes that have a full time energy to noise/vibration device.
Another experience set.
UH

What Hank said.

Craig
7Q

Another simple solution is to choose between the batteries with a simple SPDT switch, but bypass each arm with a (non-ideal) diode (regular silicon, or Schottkey). That way, (1) there is no voltage drop on the line from the battery that is chosen by the switch, (2) there is never any current flowing from one battery into the other, and (3) if you are too busy flying to notice that your chosen battery has run down, and thus fail to switch to the other battery, everything will keep running from the second battery anyway, albeit with a drop of about 0.7 volt or less (which is OK while that battery is still strong).

Disclaimer: in my glider I use a single battery, and in the rare cases where its voltage gets low, I turn off non-essential equipment (and stop yakking on the radio :-)

PS: forgot: (4) there is only a small voltage glitch when the switch is flipped.

On Friday, January 27, 2017 at 11:35:50 AM UTC-7, Andrey Lebedev wrote:
Hello group,

I did a wiring overhaul in my cockpit recently. I learned a lot in the process and decided to document my research for various ways you can connect batteries to your electronics. Hopefully this will be helpful to folks like me half a year ago.

https://medium.com/taming-a-sailplan...y-479b6632fedd

For my ship I've chosen scheme I call "Commuted circuits". I must admit I was pretty amazed by elegance of the solution.

Any feedback, especially practical experience, is highly appreciated.

--
Andrey Lebedev
WU

Has anyone tried these for power distribution? Seems like a robust solution.

https://powerwerx.com/8-position-pow...ribution-block

On Monday, January 30, 2017 at 3:31:32 PM UTC-8, Jonathan Foster wrote:

Has anyone tried these for power distribution? Seems like a robust solution.

https://powerwerx.com/8-position-pow...ribution-block

Not that part exactly, but have used the fused variety in about half a dozen instrument panels. They work great. I don't see the point in fuses on the panel.
https://powerwerx.com/west-mountain-...rigrunner-4005
Very clean, and allow you to remove an instrument and run it "on the bench" if your batteries have the same connector.
Include 15A PowerPoles by the bag (at least 25 sets), a crimp tool, and 1A, 2A and 3A fuses when you order from Powerwerx. The connectors are so easy to build that you may find yourself putting them on everything 12V.
They used to have a basic 15A connector crimp tool which worked fine. Don't see it listed any more.
Jim

No, I've used what I linked earlier.
I have used powerpole connectors for battery connections in sailplanes as well as electric RC cars. I solder them in, thus I can unsolder them and change the wires if I wish at a later date. Usually get them from a hobby place like Tower Hobbies. An alternative are Deans connectors, also from a hobby place.

On Friday, January 27, 2017 at 10:35:50 AM UTC-8, Andrey Lebedev wrote:
Hello group,

I did a wiring overhaul in my cockpit recently. I learned a lot in the process and decided to document my research for various ways you can connect batteries to your electronics. Hopefully this will be helpful to folks like me half a year ago.

https://medium.com/taming-a-sailplan...y-479b6632fedd

For my ship I've chosen scheme I call "Commuted circuits". I must admit I was pretty amazed by elegance of the solution.

Any feedback, especially practical experience, is highly appreciated.

--
Andrey Lebedev
WU

Here is an electronic battery isolator that solves all of the problems about voltage drop, cross battery current flow and switch-over glitches:

http://www.powerstream.com/DC-UPS-1212.htm

Disclaimer: I have not used this device

Tom

For power distribution I used an industrial terminal strip with a mini blade type fuse between each side. SO the 12V bus is on one side and all the connections are fused on the other side. Not exactly airplane stuff, but they are routinely used in machinery with a lot more vibration & hours than a glider normally sees.

SF