5i25 + 7i74 + 7i71 communication errors

Hi,

I have got few communication errors today with 7i71 card. Usually these come up when relays are either switched on or off any ideas why? Also should I connect PE to screw terminal near RJ45 jacks on 7i74 card? 7i71 is second from right

Tero

There were some sserial error handling bugs introduced in LinuxCNC 2.70 to 2.7.3 I would suggest first up grading to 2.7.4 if you have not already done so

In addition, the most common issue is noise introduced in the parallel cable, not the CAT5 so watch the routing of these cables
and keep them away from noise sources as much as possible

Hi,

Parallel cables are shielded and 3 feet long. Those are not routed near any other wires.... So I do not think that is issue here. Version is 2.7.4.

what actual errors are you getting?

Hi,

PCW : I did not have time to "dig into it" today. But it was communication error(13) and always with 7i71 not any other cards. Andy yes all cables are CAT5 shielded ones. And short ones either 2 or 3 feet long. And routed with 24VDC input wires (AC110V switched ones run on other side of electric cabinet). I have to restart LinuxCNC to get things running again. Also should I connect PE to screw terminal near RJ45 jacks on 7i74 card?

Tero

Card is driving these relays:

eu.mouser.com/ProductDetail/Schneider-El...odqPAciXLL5D0Q%3d%3d

Do these need flyback diodes?

If this is a noise problem its much more likely to be getting into the parallel cables than the CAT5 cables
since the signals are single ended in the parallel cable, but with the fixes in 2.7.4 a few random impulse
noise errors should not cause any trouble.

Need the actual error to figure out whats going on (communication errors are generic, the other errors give the specific cause)

one type of error that would require a restart (well really just a stop/start of sserial) would be a 7I71 remote fault