Hardinge Lathe CNC Retrofit/Conversion

[Chaz]

OK, so major progress but sadly no go.

I checked the connector and rung out the wires from the cannon plug back to the RJ45 connector (but has 10 across, not 8). All looks OK.

I then found something that explains the issues, a loose wire inside the motor. Joy of joys, would explain why the encoder doesnt work properly and why the motor heat error is needing to be masked.

So soldered it back together, sadly no change.

I did figure out how to do the the Op = 2 run again, its all in the sequence. It trips out on an encoder error. I dont remember if it did this before or not as I was getting the over temp error but I think it did the same.

Its as if the encoder is simply not working. I can see no indication of a pulse or movement.





The manual refers to checking system parameters E04 but I dont know where / what that is. It does then talk about Parameter 14_1 onwards which are for the encoder, so must be related.

Ive tried to remove the encoder to see if all wires are there but struggling to get the rear case open.

[m_c]

So you get a bit of understanding of what the drive needs to achieve, have a read of the 3 Phase Brushless Motor Control on this page - https://www.dynomotion.com/wiki/index.php/SnapAmp_Info
It is Dynomotion specific, but it explains what the drive needs to achieve.

You just then need to figure out how to do it with your drive.

Having a quick read of the manual, E02 for motor poles, E04 to set the encoder lines.
The index offset might need a bit tweaking for smooth running, but I'd expect everything else to be automatically calculated after the phase detection has run.

[Chaz]

Thanks. Ye the newer manual uses E codes, the older (which applies to mine) uses P codes.

Ive spotted that the unit might need external 24V. I dont think this is the case with mine as it has a connector going back to the SZGH control panel where it has 24V available. That said, Ive asked them to see. If there is no 24V that might explain it too but not sure where I apply it as there are no power connectors apart from 2 spare solder points (3 - one is not tinned) in the cannon jack. That wire (the untinned one) does not have a partner on the plug, so I'm wondering if that might be where 24V is inserted. Doesnt sound practical, who knows ....

[m_c]

Do you have an oscilloscope?
That would be a sure fire way to find out if the encoder is working or not.

Failing that, you could test using a multimeter connected across the encoder pairs (A+/-, then B+/-, then make sure there is at least power on the Z+/- as stopping on the Z pulse will be near impossible) and randomly positioning the motor to see if the voltages invert. That at least tells you the encoder is doing something.
And if your multimeter has frequency measuring capability, you could spin the motor and see if if you get a plausible frequency reading.

[Chaz]

Do you have an oscilloscope?
That would be a sure fire way to find out if the encoder is working or not.

Failing that, you could test using a multimeter connected across the encoder pairs (A+/-, then B+/-, then make sure there is at least power on the Z+/- as stopping on the Z pulse will be near impossible) and randomly positioning the motor to see if the voltages invert. That at least tells you the encoder is doing something.
And if your multimeter has frequency measuring capability, you could spin the motor and see if if you get a plausible frequency reading.

I dont sadly, but Ill measure with what I have. I know you can get cheap scopes for basic testing, maybe that's a plan.

[Chaz]

Nothing like spotting something, heading to the garage after 10pm, trying something, it fails, but then you see the cable that you fixed earlier still disconnected. You connect it up, you rerun the change / test and it all works.

[Chaz]

So here's a clue as to what the issue was (clearly the broken wire was also an issue).

[m_c]

I'm sorry, but I've got to say it.
Idiot!

But it just proves, always check the basics.

[Chaz]

So the cable marked with X5 DOES NOT GO into the X5P.

It goes into X2A.

I spotted in the manual that X5P = encoder OUTPUT, so I investigated further. X2A it is. I'm not sure why there is an X5 number on the cable.

The other X5 cable (X51) is also marked X5 and goes there ....

Anyways.

In fairness, there was a wire off as well, so more than 1 problem it seems.

[Chaz]

So, progress. Started to rewire and tidy up the cabinet.

First test cut (well, 2nd), - ignore the birds nesting, bad feeds / speeds.

I need to work out why the spindle override is being ignored too. Speeds are being set by G50 S2000 etc. Need to see the details behind this, I'm using the Fanuc Post Processor.



And then a pic, I missed facing it fully but you get the idea, really happy with this.