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Stall warning switch

whity1231$

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I think I am going to have to replace my stall warning switch. I can’t get continuity between the two wires with the switch activated. Does anyone know what the voltage on the terminal wire is? I am only getting 10.6 volts? I am thinking it will be easier to take the wing off so that my old arms and hands can work in a more comfortable position up in the little access door. Any ideas appreciated.
 
I think you should have continuity between the two wires with the switch not activated.

Normally closed

I think I am going to have to replace my stall warning switch. I can’t get continuity between the two wires with the switch activated. Does anyone know what the voltage on the terminal wire is? I am only getting 10.6 volts? I am thinking it will be easier to take the wing off so that my old arms and hands can work in a more comfortable position up in the little access door. Any ideas appreciated.
 
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The voltage on the sense wire to the stall warner switch from the module is not published as far as I know, but 10.6 volts doesn't seem bad. Vans support may know that technical detail specification.

There should be continuity between the switch "common" and "normally open" terminals when the vane is activated up.

The idea to take off the wing and place it upside down on some padded saw horses will make it easier to reach.

It will also help to have a large dental type inspection mirror and a LED work light to put inside.
 
Is your stall warning switch wired to your G3X or is it a buzzer?

My switch is grounded and goes open in a stall on my G3X discrete


I think I am going to have to replace my stall warning switch. I can’t get continuity between the two wires with the switch activated. Does anyone know what the voltage on the terminal wire is? I am only getting 10.6 volts? I am thinking it will be easier to take the wing off so that my old arms and hands can work in a more comfortable position up in the little access door. Any ideas appreciated.
 
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On a plan's built E-LSA RV-12 with Dynon avionics the stall switch in the wing is wired normally open and when the vane is activated UP it closes the switch and grounds the sense wire.
 

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Can you hear the switch click as the vane is moved up and down.
If not, the bracket might need to be adjusted. Two screws hold it to a rib.
The top screw hole is slotted. The bottom hole is round.
Loosen both screws one half turn to adjust the mounting bracket.
 
Do you have the AOA feature installed? I’ve thought about just removing mine. Two buddies who are building a 7 and a Sonex didn’t even install a stall warning switch.
 
No I don’t have a AoA installed. Would be a lot of work and expense to install on 2011 RV 12 with Dynon 180.

Not at all. One rivet in the wing, one tube to the back of the D180. I did mine well before Van's came out with the kit to do the tubing through the wing connector with a quick disconnect; I used a twist lock fitting (Luer lock). Calibration of the D180 is pretty straightforward. We've been flying with AoA for several years now and like it a lot better than the stall warning vane and switch.
 
Expensive? The AOA port is a SD-42-BSLF Blind Rivet available from Van's for $0.08
I glued the rivet in place instead of pulling it.
I used soft, highly flexible, 1/8 inch O.D. plastic tubing between the rivet and the D-180.
And I used sports ball inflating needles with the threaded end cut off.
One needle, through a hollow bolt, makes a coupling at the wing root. The other needle,
soldered into a brass plug, connects to the back of the D-180. Shipping will cost more than the parts.
To minimize labor, I ran the tubing inside of the cockpit along the left side of the fuselage.
Use a wire stripper to push the tubing off from the needle when required.
If pulled, the tubing grips harder like a Chinese finger.
 
+1 for Dale's response. Not that hard. I like being able to see how much "reserve lift" I have available well in advance of a stall.
 
Stall switch

Thanks for the information. I didn’t realize that simple of system was available. Is what you described, the same as what I now see Van’s offering for $60(on back order)? Next condition inspection I might do this
 
I have flown one aircraft that had AOA. Nice but never considered it vital. My stall warning in my 12 died a few years ago, and I never bothered to fix it. The only time I ever had a near stall in 37 years of flying was also the only time I ever got into an unusual attitude. I was spiral climbing through a sucker hole VFR in my Cherokee. I glanced at my airspeed decaying rapidly and went to my AI which showed a very nose high attitude. Immediately recovered to level flight. I am a firm believer in making an instrument scan a constant part of flying. AOA is nice, but paying constant attention to flight instruments is a great way to prevent stalls.
 
Just done the fly off of a 12 here. Had to adjust the stall warner but that was sorted. Calibrated the AoA and I agree - Waaaaaay better than a buzzer.

Fly AoA in our 7 - much more accurate.
 
If you have an older model RV12 they used screw heads to be the contact points for your Nav lights and stall warning switch. Later they came out with a socket type connector. When I bought my -12 I had issues with this and instead of going to the socket type I installed a connector plug with about a 12" coil of encased wire. Works great no connection issues, however you must remember to unplug when removing wings, I noted this in my M/M as a revised method.
 
Thanks for the information. I didn’t realize that simple of system was available. Is what you described, the same as what I now see Van’s offering for $60(on back order)? Next condition inspection I might do this
The Van's solution is a bit more elegant, in that it includes a quick disconnect thingie at the wing root. On mine you slide the wing out a few inches and disconnect the twist lock connector. It really only comes into play once a year at most. The D180 has an AoA port on the back of the unit, you just need to run a tube out through the wing to a strategically located port (the blind rivet minus its mandrel).

I wasn't the one who figured this out; someone way smarter than me did that and I read about it here (https://vansairforce.net/community/showthread.php?t=34040&highlight=aoa&page=2).
 
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