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I am guessing I am having a noise problem. The output of the 0 to 10 volts of the axbb-e controller is fluctuating. I can't seem to figure out whats going on , I have tested the input from the 5 volt and 24 volt power supplies and there is 0 fluctuations in voltage. It's enough of a fluctuation that the voltage affects the spindle output with a variance of about 500 to 800 RPM.

I've put a multi meter on AO1 and 5v0 and you can see the voltage go up and down, how would one find out what's going on.

The controller is in a different enclosure from the VFD, about 3m apart.

If you unconnect the analog output and measuring on the A01 and 5V0 then the voltage is still fluctating?

When removing the cable from the axbbe that runs to the VFD there is zero fluctuation and the voltages are spot on.

I have the shield grounded at the controller side, is this ok or should it be ground at VFD side instead?

What do I do to make signal stable when wired in? Add a 100uf on axbbe and VFD?

Thanks

It looks like then that the VFD analog input circuit makes the signal to fluctate.
Yes, you can try to add some buffering to the signal.
Add a 100uF capacitor to between the signal and it's ground at the VFD side.
Also you can add a small ceramic capacitor in parallel, a few 100nF to filter high frequency noise.

Would the + leg of the 100mf cap connect to the signal side or is the polarization of the capacitor irelavent if it's an electolytic ?
Thanks
Andrew

nop mF, but uF, m is milli and u is micro, milli is 1000 times larger.

For electrolit caps the polarity is important, for ceramics it is not.