rotary encoder strange behaviour (non-grey code?)

Other Hardware General Electronics
1

I have bought a bunch of encoders to use in my projects but they seem to behave in an unusual way (for me at least)
I made a screenshot of my logic analyser showing the anomaly.
The first two channels show the encoder in question the other two showing another encoder pruducing right gray code. (how i think it should be)
I tried two if the same encoder to be sure but both shows the same problem.

I don't have a real datasheet for them either.
Is this not a "normal" quadratic encoder? Maybe i wired it up the wrong way?
The pulse on channel 2 is really short too like 5 ms.
Have anyone seen something like this?

encoder.png
encoder.png622×732 5.74 KB

2

Original picture...

8d5d93cf1124cd72e8a03ccee25410c6095aa23b.png
8d5d93cf1124cd72e8a03ccee25410c6095aa23b.png622×732 5.74 KB

3

If you have an analog scope, then look at the waveforms. It might be something weird like a capacitor in the output.

I would suggest that it's broken and you should try another one.

4

Thank you for your answer and for posting the picture.
Well, i tried 3 encoders now and i get the same result. Unfortunately i don't have an oscilloscope and neither have access to one. :confused:

One thing i forgot to mention is that the falling edges are perfectly aligned! If i turn the encoder in the other direction then the rising edges get aligned. I can not measure any difference at the highest resolution. It seems like the other half of channel 2 is cut off at start or end of channel 1s periods.

All the encoders have the same fault? They are from a somewhat reputable source and sold out now.

5

Do you have a spec for the encoders? And a circuit diagram?

Allan

6

Well this is embarrassing but... Yes I WIRED IT UP WRONG. The common pin was not the one in the middle. If i learned something today, always look at the datasheet and if you don't have one, get one.
If someone does the same now can find this post as attrition.

7

Contrition? else you're wearing me out.

Allan

8

piel:
If i learned something today, always look at the datasheet and if you don't have one, get one.

Double checking every pinout is well worth the effort, even with the datasheet in front of you! The principle
of "check twice, buy once"

9

After over 30 years of electronics, I still wire things up wrong when I rush. Blew an arduino a couple of days ago due to this.

10

piel:
Well this is embarrassing but... Yes I WIRED IT UP WRONG. The common pin was not the one in the middle. If i learned something today, always look at the datasheet and if you don't have one, get one.
If someone does the same now can find this post as attrition.

Yes, true. It is ok to assume certain things if it is known in general that components of a particular kind are always configured in the same way - same pinouts etc. But when we don't know that..... then avoid assuming, or going into an autopilot mode.