Show Posts

This section allows you to view all posts made by this member. Note that you can only see posts made in areas you currently have access to.


Topics - BLF_Electronics

Pages: [1]
1
Technical support / PID question
« on: November 04, 2005, 09:00:08 AM »
I need to use 10 channels of the PID. I used the PIDdef to define all ten channels. When I attempt to run the code and it gets to the following line I get an error message with the 9 highlighted. Has anyone attempted to use this many PID channels? The manual states 16 channels are available. The first eight work fine. Any comments will be appreciated.

DM[D+6] = PIDcompute(9,DM[D+5])

Error: Unknown Keyword


2
Technical support / Stepper Motor control question
« on: December 16, 2003, 07:26:18 AM »
I have a question using the Stepper control with the T100MD+ PLC. I am using the stepspeed command in a dCust function to setup the initial move parameters with the default values I am storing them in the DM variables as follows.

DM[1] = 5000 'Pulses Per Second
DM[2] = 100   'Steps to reach full speed
DM[3] = 500   'Default Forward pulses per move
DM[4] = -500  'Default Reverse pulses per move
DM[5] = 2     'Default Delay time between moves
DM[6] = 20     'Default number of moves

stepspeed 1,DM[1],DM[2]

I then issue a stepmove command in another dCust function based on logic that looks at the time delay between moves after the step complete relay becomes true.

stepmove 1,DM[3],10

Everything works fine until I set the pulses per second up to 5000. At that point I get some oscillation in the stepper motor and it may stall. I am using a SilverPak integrated step motor and driver from Lin Engineering that is good up to 20Khz as the max step frequency. The specs also say the minimum step low time is 20 microseconds which should not be a problem at the 5000 pps setting. Am I doing anything that appears incorrect and do you have any ideas? I have also moved the motor only one move at the 5000 pps and get the same results. Everything works fine at a slower pps.

Thanks,

Brian Ferry

Pages: [1]