Electrical Noise Causing Axis Jumps

I am pretty sure on your picture those are UTP cables on the encoders, not the original ones.
Use STP of SFTP cable and wire the shield to ground only on the Mesa side, leave encoder side unconnected.

jlennox wrote:

As I get random estops when the spindle runs I suspect I am getting noise on the 10v signal lines as well as my inputs. Would the following scenarios be possible:
- Issue with the 24v power supply generating noise as a result of noise on the AC line due to spindle drive?
-  My 0-10v analog signals wires are just single core cables I twisted as pairs (see wires labeled ER(R)1, ER(R)2, etc in first post), despite the short run, could noise be introduced on them and am I better off swapping to shielded twisted cable? This wouldnt explain random estops as those would have to be from noise on inputs.
 

Why and how do you get random E-STOPs? I supposed the machine stopped because it thought an axis "jumped" outside of machine limits, but that seems not to be the case. If you have electrical issues with ESTOP triggering via noise, fix that first. E-STOP usually is a loop of "N"ormally "C"losed switches that open when actuated. This way broken or faulty ESTOP chain won't let you activate the machine. Hard to imagine you can influence that with induced noise?
Check for loose connections and if everything is grounded properly. Differential signals also need ground (usually).
If you can use an oscilloscope, check signals with spindle on/off, but be careful to connect probe gnd very near where you pick up the signal. 

jlennox wrote:

-  My 0-10v analog signals wires are just single core cables I twisted as pairs (see wires labeled ER(R)1, ER(R)2, etc in first post), despite the short run, could noise be introduced on them and am I better off swapping to shielded twisted cable?

 

Also must be shielded, but if this was the issue, the machine would jump a lot, so i do not think this is a problem for now.

jlennox wrote:

As I get random estops when the spindle runs I suspect I am getting noise on the 10v signal lines as well as my inputs.  

This for sure means something is very wrong with grounding/shielding on the wiring.
Start from the beginning:
Does the shop have proper grounding?
Does the machine have grounding wired properly?
Does the shop have a FID or GFR of whatever the name of the thing that cuts the power to the shop if anything goes wrong with the grounding?
These are a must, there is no way around it.
And just in case, change the power supply for Mesa, a while back had a very noisy one.

rmu wrote:

Why and how do you get random E-STOPs? 

Generally through noise on a limit switch input. 

I generally debounce the limit switches, as nuisance tripping can be expensive, whereas a 10ms delay in tripping the limit switches probably doesn't matter that much. 
 

andypugh wrote:

rmu wrote:

Why and how do you get random E-STOPs? 

Generally through noise on a limit switch input. 

I generally debounce the limit switches, as nuisance tripping can be expensive, whereas a 10ms delay in tripping the limit switches probably doesn't matter that much. 
 

But that is not a general "E-Stop", linuxcnc complains "axis limit exceeded" or something like that.

Andy, I managed to find a RFI filter available local to aus, made by Fuji but has the exact same part number a the Rasmi filters, going to pick it up and install.

Tommylight, I have attached a photo of my new control rack (note this photo doesnt show the encoder wires to the mesacard as in the first post photos). The encoder wiring goes as such; everything is square brackets is inside of my new control rack.
Encoder -> Existing resolver wires (shielded twisted pairs for A/A', B/B' and 5v/Gnd) -> [ MR20 Breakout Board -> UTP cable (using 3 pairs)  -> Mesa 7i77 ]
Do you believe it's possible I am getting noise on the utp cables? They only run 400mm inside the new control rack. I have also orderded shielded twisted pair cable for the 0-10v signals.
You also make a good point on building grounding, my machine lives at my work place and guys running previous machines (robotics and automation company)  have said they have routinly encountered noise issues directly related to grounding, something i'll need to investigate.

RMU, apologies, they a random machine enable dropouts, not full e-stop. As the majority of sensors go through classic ladder fist to replicate a lot of the original machine plc code, it is hard to determine what is exactly tripping it, I am assuming limit switches or something lower level as all the critical e-stops have a gmoccapy message tied to them so would show. I could set a timer up in classic ladder to be able to catch these as they happy too fast normally.


I am sadly out for a week or so (family destruction expansion) but will install an EMI filter when i'm at the machine next and test each 24v PSU (two in machine, one for control rack once for sensors & switches) with a scope and see what the noise looks like before the emi filter goes in, would really like to know the cuplrit rather than 'covreing' it with the emi filter.

Cheers for the help so far guys.