New Build King Rich KRV-3000 Knee Mill with GSK AC Servos DA98B driver

[dmbgo]

I've renamed this post with the heading "New Build" because that's what it is. I hope I get this running soon, I'm keen to purchase and try out the full mill centroid package.
The issues above are unchanged at the moment, but I'm sure someone will help me soon with the config of the AC servos

[dmbgo]

I've renamed this post with the heading "New Build" because that's what it is. I hope I get this running soon, I'm keen to purchase and try out the full mill centroid package.
The issues above are unchanged at the moment, but I'm sure someone will help me soon with the config of the AC servos

[dmbgo]

Cnckeith, I haven't heard anything from Chuck yet.
This morning I thought I might connect the DA98B AC servo driver and motor back onto the Gsk 980MDa controller, I know it works there. I can use the meter to measure the signals etc. Doing this might enable me to look at the differences between the Acorn and the GSK controller.

[dmbgo]

This morning I made a DB15 male to female connector from 2 x db15 break out boards. I wanted to put it on the mill, in line with the existing cable to the servo that I have been trying to make work on the Acorn.

This would expose the connections and enable me to compare the signals etc on a working setup, with the Acorn setup that I am building.
Initially I made the DB15 male to female connector with all of the pins connected, so that I could ensure that it was going to work - it did work as expected.
Then I removed some of the wires, leaving only those that were connected in the diagram that I took from the GSK 980MDa manual. Guess what, it no longer worked. The GSK cable, wasn't the same as the example that they had in the 980MDa manual (Grrr).
I then pulled the original cable apart and found an extra connection, that wasn't in the diagram, it was DB15 pin 14, which was connected to DB44 pin 23 (SON).
I also noticed that the servo was locked at power up, when connected to the 980MDa but not when I had it connected to the Acorn.
This brings me up to the present. The next step is to go back to the Acorn, armed with extra knowledge. Wish me luck....

[dmbgo]

Still no movement from the servo (Sigh). When I connect the missing wire to Acorn 0v, the servo locks, the same as it does on the GSK controller, but it still doesn't rotate. I played around switching the step signal from a positive location to a negative one, but no change. I'd be really grateful for some help with this

[dmbgo]

Just wondering what voltage is the Acorn step output?
I'm wondering as well, how the servo behaves with only one side of it's normal step and direction signal, does it just work anyway it is there something I need to do to the acorn signal?

[dmbgo]

Just wondering what voltage is the Acorn step output?
I'm wondering as well, how the servo behaves with only one side of it's normal step and direction signal, does it just work anyway it is there something I need to do to the acorn signal?

[suntravel]

DB25 is 5V, Headers are 24V by default

Uwe

[dmbgo]

Thanks Uwe, I'm using the Acorn headers, so the output pulse from the Acorn is 24v. Now I need to know if there are any issues with the single pulse from the Acorn, rather than a + and - one that the DA98B expects.
Also I haven'yet checked things like the pulse frequency that the controller expects either. I'm also unsure whether inverting the pulse etc, would stop the motor from turning, or rather be something that can be changed after things start to work.

[cncsnw]

Just to avoid perpetuating a common misunderstanding:

The Acorn axis headers do not supply 24V.
The Acorn axis headers do not require 24V.

The Acorn axis headers are open-collector outputs, which when active provide a path to 0V/COM. I.e. there are "sinking" outputs. It is up to the servo drive or your external wiring to provide a positive voltage for them to sink. That externally-applied voltage may be +24V, but it does not have to be.

Any current-limiting resistors, which would be sized dependent on the applied voltage, are in the servo drive. They are associated with the drives' opto-couplers; not with the Acorn's outputs.