Panasonic MSD AC Servo - anyone ever fitted/setup one - manual driving me insane.HELP

[Nemo1966]

OK so got 3 of these on a Denford Triac. Trying to get them running (nearly there) but the manual is driving me insane.
In this picture (from the manual)...

31058

So in the picture I assume it shows the starting state of the servo connections before the "Trial Run". (page 24 - 25 in the manual)

It shows:
"Servo ON" as OFF (open switch)
"CL" as ON (closed switch)
"INH" as OFF (open switch)

But then in the instructions it states - "Make a deviation counter clear (CL) signal to clear release [B](L -> H)."???? So I am assuming the "ON" state at the start is "LOW". I would have assumed "LOW" was OFF ?????

Also when it says signal to clear release - I assume this is flip the switch???? Not flip it on and off to reset a counter????

Do I have to run through this procedure everytime I start the servos??? Seems strange.

Anyone please... the manual is driving me nuts.?

Thanks

Manual -> https://www.airgunownersclub.co.uk/downloads/MINAS-Xseries_manual_e.pdf

[Doddy]

So, going though your questions as I see them one-by-one:

"Assuming LOW was OFF?", why? - the inputs to the controller are designed to sink current - examine the functional schematic in the manual - the cathode of the LED/Opto-Isolator is presented at the signal input. Connecting this to ground (through a switch, or an open-collector output from a motion controller) allows current through the LED and the input is considered "active" (or "On").

"Not flip it on and off to reset the counter?" Think of what is being attempted here. You have a servo that you're commissioning, from power-up you might justifiably expect the deviation counter to be reset... of course, any movement of the spindle would "clock" the deviation counter. If you didn't clear the deviation counter then the servo controller could either enter the Alarm-phase, or spin the servo unexpectedly to recover the servo position. Read page 19 - function of "CL" - when "Low" (active) - this clears the deviation counter and inhibits the servo position pulse inputs. Implicitly on transition to High / open circuit, those inputs are enabled. So, all this is saying is, start with the CL input low to ensure that the deviation counter is clear. Once you're ready to test the servo then de-assert the CLear input and off you go. It's up to you to decide how to use this input in future - it could be that you want to wire-or (connect each of the servo driver's inputs) together and wire to a motion controller OC output, tied to a button on the UI. I'm a long way from my two machines with servos to check, but I'm 99% convinced that I've left these inputs unconnected (caveated by I'm running my servos as spindles, not axis motion),

"Do I have to run...." - understand the purpose of this clear-deviation counter signal (and the deviation counter), and answer that question for yourself.

[Nemo1966]

So, going though your questions as I see them one-by-one:

"Assuming LOW was OFF?", why? - the inputs to the controller are designed to sink current - examine the functional schematic in the manual - the cathode of the LED/Opto-Isolator is presented at the signal input. Connecting this to ground (through a switch, or an open-collector output from a motion controller) allows current through the LED and the input is considered "active" (or "On").

I think this is the crux of my problem in this area. I always thought in electronics that HIGH = ON = ACTIVE. Even with a "sinking" current, you have to supply a high/active/on signal to the transistor to make it sink. Great explanation - greatly appreciated.




"Not flip it on and off to reset the counter?" Think of what is being attempted here. You have a servo that you're commissioning, from power-up you might justifiably expect the deviation counter to be reset... of course, any movement of the spindle would "clock" the deviation counter. If you didn't clear the deviation counter then the servo controller could either enter the Alarm-phase, or spin the servo unexpectedly to recover the servo position. Read page 19 - function of "CL" - when "Low" (active) - this clears the deviation counter and inhibits the servo position pulse inputs. Implicitly on transition to High / open circuit, those inputs are enabled. So, all this is saying is, start with the CL input low to ensure that the deviation counter is clear. Once you're ready to test the servo then de-assert the CLear input and off you go. It's up to you to decide how to use this input in future - it could be that you want to wire-or (connect each of the servo driver's inputs) together and wire to a motion controller OC output, tied to a button on the UI. I'm a long way from my two machines with servos to check, but I'm 99% convinced that I've left these inputs unconnected (caveated by I'm running my servos as spindles, not axis motion),

Outstanding - once this is explained it all makes sense. Thank you again.

As I see it now, the devation counter should be cleared on startup, just in case the spindle has moved etc whilst the machine was off. (as you said).

Now the INH on Page 19 states it inhibits the Pulse/SIG when you turn it to "H" (which is an open switch). Now this is obviously the default settings for the switch as the user has to close it to make it "LOW". This is probably why mine won't run as it has always been HIGH (open switch).

Regarding CW and CCW it seems these switches are negated by a parameter.

Thanks!!!