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Parking brake valve position sensor

No idea but my guess is it would be exceedingly uncommon and most would simply use the position of the cable handle as said indicator. Anecdotally I've used my parking break a grand total or twice in 10 years and one those was just a test of the system. However, I know there's others that use their's all of the time.
 
I went for years without parking brake, but one day while struggling to get out and chock wheels without rolling off the ramp, I decided to add one. Use it here and there but when I use it I am glad to have it.
I just use the control position to indicate status. It you want a warning in a display system, a micro switch could be rigged.
 
This can easily be done, especially in a Garmin G3X system with multiple user-configurable discrete inputs.

I installed a microswitch on the Matco parking brake valve arm. It is connected to an active low discrete input on my G3X system (GEA24 or GAD27). When the parking brake is on, the microswitch grounds the circuit, and the CAS generates a "Parking Brake On" alert on the G3X screen.

It is a small bit of extra work, a minor enhancement at best, and not really necessary of course.

The microswitch can be obtained from the usual electronics supply places. It is the same one I used to give a “Canopy Open” alert on the G3X screen.
 

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Not Matco but principle the same, micro switch to a discrete labeled Parking Brake On" in the G3X. Probably overkill but I would not want to land with the PB on.
 
This can easily be done, especially in a Garmin G3X system with multiple user-configurable discrete inputs.

I installed a microswitch on the Matco parking brake valve arm. It is connected it to an active low discrete input on my G3X system (GEA24 or GAD27). When the parking brake is on, the microswitch grounds the circuit, and the CAS generates a "Parking Brake On" alert on the G3X screen.

It is a small bit of extra work, a minor enhancement at best, and not really necessary of course.

The microswitch can be obtained from the usual electronics supply places. It is the same one I used to give a “Canopy Open” alert on the G3X screen.
Thanks for the pics!, I was thinking something like this, just trying to avoid multiple iterations before finding a configuration that works.
 
Here's my version. Took a bit of effort to get the rigging correct so it doesn't nuisance show "not fully off". I also had to change the push/pull cable to the type with a pushbutton to keep it from creeping out and triggering the microswitch.
-Bob
 

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I did similar to the ones posted above. When not fully open the switch pulls to ground and shows on the G3X. Mine's a taildragger and if you land with the parking brake on it's almost certainly going to face plant, so I placed a high priority on it having a CAS message.
 

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Has anyone added a switch on the Matco parking brake valve to indicate valve position?
I used a small microswitch to illuminate a red LED mounted above my Garmin display when the parking brake is engaged.
 

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I had some additional "hat" section of material from the canopy release system and used that to create a place to mount the brake valve. Nutplates on the back of the hat section hold the bolts that go through the brake valve body. A piece of aluminum sheet with a "V" cut out allows the arm to move from open to closed on the brake valve.

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Mounted on the firewall
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Added a microswitch with a small spacer for alignment with the arm that closes the circuit when the brake is on.
The Dynon EMS gets this input and displays the status of the parking brake on the EFIS.

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Looks like a lot of people did this! Mine is exactly the same as Bob's design with the microswitch. My pull cable is tucked a little out of the way, so I thought it would be useful to have a CAS message for it.
 
Thanks for all the great advice. My preference is to have the switch set to advise when the park brake is not fully released.
This will protect me from cable failure, since my set up is push to relase, or inadvertently landing with the brake on. I also put the knob very close to the throttle lever.
Due to the long valve lever motion. It is difficult to have one light that can show if the valve is fully closed or fully open.
Of course, for more overkill, I could put 2 switches on it and monitor both positions!
 
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