E4T Encoder stop working after couple runs

I’ve been fighting with this for the past week, hope someone can help. We started to use E4T on the FTC robot this year, connect them to the REV Expansion Hub through 3.3v to 5v Level Shifter. We have 3 of them, left, right and horizontal. One of three kept having problems, it would work for a while (say 30 minutes), then suddenly stopped working, always 0 counts. If I tried a different E4T on the same cable, I got counts. I let it sit over night, it may work again next day for a while, and then stopped again. I swapped out the encoder to a brand new one, it worked for a while, then same thing happened. Eventually, one of the E4T, even after overnight, won’t work anymore, completed dead. Have you folks seen this before?

Strange that always the same left one has problem, the other two wheels are fine. I am going to try it on a different port next to see it makes a difference.

The E4T is notorious for going bad under some type of heavy shock (i.e. use in drivetrain, etc.). It is a very high quality encoder in systems WITHOUT lots of shock, but if possible I would recommend using an entirely different encoder for your purpose, which while not explicitly stated, seems to likely be your drivetrain. I recommend the AMT-103V, which is cheap and sturdy, and has a proven record of reliability for FIRST purposes

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If you want to stay in the US Digital miniature encoder ecosystem, I recommend getting S4T encoders, we had a lot of reliability issues with the E4T encoders in the past too.

Thanks @juju_beans and @Tomithy. I am going to try the AMT one right away, seems like a simple swap with the E4T. The S4T is too expensive (somewhere I read it’s actually a E4T inside), and a redesign of the wheel/encoder setup is needed.

It’s an E4T but with an integrated shaft. The non integrated shaft is where the problems from the E4T encoders arise from. I’m not sure why it would require a redesign though, as these 2 encoders can be easily swapped out in place of each other by attaching a surgical tubing to the .25" shaft. (see pic:

We have to fit the whole thing into a small channel on the bot, even E4T barely fits, I had to sand the cap off a bit. That’s why AMT102-V may fit (it’s a bit too wide, but maybe still ok). If use S4T, will just put the wheel onto the S4T axle directly.

thanks!
haifeng