Cheap & nasty chinese servo drives

[HughF]

Does anyone have any real-world interfacing experience with 'Lichuan' brand servo drives? I'm building a prototype mecatronics project with one and am having some issues with the encoder output from the drive.

 

[Hood]

@Davek0974 recently retrofitted a Bridgeport with Chinese servos, whether they were the same or similar I have no idea but ....

 

[Maxakarudy]

if you don't get the answer on here try this forum.....http://www.mycncuk.com/

 

[Davek0974]

Lichuan drives look similar but not the same, no idea about the internals

What sort of encoder issues are you having?

Have you used twisted-pair cable?

 

[HughF]

Just found the problem.... The encoder-out from the drive (we need to get access to this for our motion control system) had a horrible mains noise/wobble on it. Turns out the 'gnd' on the digital IO connector isn't actually a decent ground, it's the chassis earth which is neutral/earth bonded.

Moved my logic ground onto the 'gnd' that feeds the motor encoder, all is now sweet.

I'll email Jessie @ Lichuan when she's back from new year and tell her to fix her datasheet

 

[MattH]

 

[HughF]

Literally a week of head scratching....

 

[Davek0974]

Nice fix