How to Test Optocouplers (Spindle)

[metzenovich]

Hi,

I'm trying to test the optocouplers (pins 4/5 and 6/7 on the spindle controls) on my Masso G3.

My VFD wants the Fwd and Rev pins grounded to control direction. If I jump a wire between Fwd and Gnd while the 0-10v analog input has some voltage on it the spindle turns on. Removing the jumper and running Fwd to ground through pins 4/5 or 6/7 on the Masso spindle connector doesn't do anything.

How can I test the optocouplers to see if they need to be replaced?

This link is no longer active (it looks like the documentation was recently replaced / updated):

Welcome to the MASSO documentation

www.masso.com.au

In the meantime it looks like my best option to get up and running is to use a relay triggered by pin 2 or pin 3 of the Masso spindle connector to ground the Fwd and Rev pins for me.

Thanks!

 

[masso-support]

Hi Metzenovich

Just a few notes that might help find your issue. You don't mention what type of VFD you have so the below is just my initial thoughts.

• Masso FWD & REV will not turn on if you do not give a speed command even if you have not connected the speed control yet. eg enter S10000 in MDI
  
• The spindle control pins 4/5 & 6/7 are polarity conscious so just check the polarity of the VFD, FWD & REV as it might use positive ground and not negative.
  
• The chances of both optocouples being faulty are very slim indeed.
  
• If you use a relay on pins 2 & 3 it must be a TTL relay
  

To test put your multimeter in continuity mode on a high resistance scale like the 20K scale
Put the meter across 6&7 for CCW or 4&5 for CW depending on which one you want to measure
Manually turn on the optocouple by going to the F1 screen, highlight the CW or CCW and press the spacebar to toggle the output status. (This bypasses the need for a spindle speed command)
High will measure about 3K or 0.4K depending on your meter polarity
Low will not show a reading as the circuit is open

See if any of these helps get you going before looking at replacing the optocouplers.
Have you watched and followed the process outlined in the VFD install video? It takes you through step by step and from the looks of it you are almost there but there are a couple of things like testing VFD polarity that you might have missed.
https://docs.masso.com.au/wiring-and-setup/setup-and-calibration/spindle-vfd-examples

Let us know what you find.
Cheers Peter

 

[metzenovich]

Thanks, Peter.

The VFD looks like the Yuhuan Huanyang on your website, but without the built-in potentiometer (knob). It's a model A2-8075 by Isacon Power Control (I think it's probably a Yuhuan Huanyang knock-off).

I'll have to check the polarity. I could have sworn I had it working through Masso a few months ago, but I'm just now getting back to the CNC.

I now have it working using TTL relays triggered by pins 2 & 3, which works fine. Just because I had some on hand. I may still try to get it working through the optocouplers just to know they still work (and because it would be simpler, less wiring, and two less things to break). I'll test using a multimeter first. Thanks for the instructions.

So my VFD is working.

Thank you.

Next step: actually cut something...