[DeanW]

I am going to use KFlop Step/Dir to Yaskawa SGDH servo drives in Position Mode for a vertical mill retrofit. These drives have outputs for differential encoder signals which I could send (singles) to KFlop. I have searched through the forums and I have read one opinion that there is no need to send the encoder signals to KFlop. But, I also read the KFlop can use encoder signals to keep position under certain fault conditions. Perhaps this is only desirable if you have glass scales etc. that are separate from the motor / drive electronics?

The Yaskawa motors have serial encoders, so I cannot power them separately - the only way I can get signals is through the drives.
If an E-Stop shuts down the drives, the encoder signals would stop. Perhaps a drive fault might stop the signals also?
I am not sure if only disabling the drives for E-Stop would be safe.
I have more research to do. I plan on using a Safety Relay and safe E-Stop practices.

Is there any benefit to having KFlop read the passed on encoder signals from Position Mode servo drives like these?
What E-Stop / fault wiring would be needed?

TIA

[TomKerekes]

Hi Dean,

The main advantage of feeding the encoder signals back to KFLOP is so that you can observe and plot the motion performance in KMotion.exe. KFLOP can also watch for following errors. And as you state if the amplifier is disabled then KFLOP can still keep track of the position and the system can later re-initialize and still know where everything is. I'm not sure what you mean when you say "If an E-Stop shuts down the drives the encoder signals would stop". The encoder signals would usually not stop and would still track any final motion. Unless you mean that when the motors finally stop the encoders will obviously stop counting.

Since a hardware EStop or a fault will usually immediately generate a following error (or certainly will as soon as some motion is attempted) it usually isn't necessary to wire all Estop and Amplifier status back to KFLOP. But it is always nice to have the additional information.

HTH
Regards
TK

[DeanW]

>>"If an E-Stop shuts down the drives the encoder signals would stop"
I was thinking that the drive may not pass on encoder signals when disabled. But, it sounds like you are saying it should... so no problem.

OK, I will connect them.

Thanks.

[DeanW]

Thanks for all of your help Tom.

I probably have the parts to interface these (and home switches etc) but I know KAnalog will be a cleaner and easier solution.
So, I just now purchased your KAnalog board. You deserve the business.
I plan to use the opto ins for the home switches and the diff encoder inputs for these Yaskawa drive encoder out signals.

Now, I will start my wiring/connection plans over to utilize the KAnalog.

Thanks again for providing great products and support.

Dean