Phidgets Forums

Hello, sorry for my poor english, I'm french.
I bought a touch sensor 1129-1A.
I've got this result when I try it:
- first, SensorValue is 0
- When I touch it, SensorValue is 1 and stay on 1 even I release
- Now, when I touch SensorValue is 0 and goes to 1 when I release
- After 45s, SensorValue goes from 1 to 0
I don't know if it is normal but it isn't convenient for me.
Because, I need the same value when I touch and the opposite value when I release.
Thanks.

When you first touch it, how long is the contact? If it's longer than 45s, then it'll recalibrate and treat this as "0" and then when you remove it'll register that as different from the "new normal" and go to 1 for 45s until it recalibrates back to 0.

If it's just a brief touch then the only other thing I can think of is maybe there's something on the surface of the 1129 that can carry charge and interfere (a drop of water, or a strand of fabric for example). Does this behaviour happen all of the time, or just some of the time? Does it happen when you don't actually touch the surface and just bring your finger close to it?

Hello, thank you for your answer.
I tried again to verify. In all cases, I had the same result.
The first time I touch it, it stay in 1 during 45s.
I tried with the touch sensor out of any surface. I tried with no touch, just proximity. I tried with addition of a piece of copper. It worked always like I described.
Do you think it is out of order?
I'm surprise by its reference: 1129-1A (a little "A" above the "1"), I don't see this ref on your website.
I bought it at Gotronic in France.
Have a good day.

The "A" on the board is just a minor hardware revision- we don't list it on the website because it's usually just small changes in component placement and the like.

Do you see any signs of damage on any of the components on the board?

No, I don't see any damage on it.

Are you using the Phidget Control Panel to test it, or some other program? Using the control panel will rule out any potential coding errors.

Yes I test with Phidget Control Panel. I use a wireless VINT Hub HUB5000.
I received a new 1129-1A from Gotronic but the result is the same.
The first time I touch it goes to 1 and stay 1. Then, it works (touch => 0, release => 1) as long as I touch it one time in less than 45s.

I did some testing with my own 1129 and found I was able to get a similar result sometimes if the device was flat side down on my desk. The problem is that the sensor is very sensitive and it needs to be securely mounted, because even a small change in movement can cause the capacitance in the environment to shift. Can you try mounting the 1129 securely face-up and see if it still behaves this way?

Thank you for your test.
I tried to secure the sensor on a piece of wood and far from my laptop but I've got the same result. I don't understand.

We tried again to replicate your results, but still can't get the sensor to get stuck like you're describing. Does it behave this way when you test it in a different location?