How to control my spindle motor (Clipper board)

Hi I have a Pmac Clipper board. I want to know how to set I variables to get my spindle running (milling spindle). The spindle motor is controlled by a frequency inverter. I'm using motor #6 DAC differential ended output connected to the inverter using +/-10V and GND. The spindle has no feedback, the spindle must run in open loop mode. I have set these I variables: I600=1 I602=$78102 I7126=1 Is this right and are there more I variables I need to set ? Thanks ! Jorgen

Jorgen, The Clipper board is a Turbo PMAC2, purely digital card. The DAC output is obtained by filtering the PWM signal. This is normally done by setting the PWM frequency around 30 KHz, this will give you a nice sine wave (analog) output. Things to keep in mind: - Since you are using axis 6, these settings will apply on servo IC #1 thus axis-5 through 8. None of these channels can now be used for standard PWM control. - Servo IC #0, by default, is your clock master (generator, set by I19). The PWM frequency of Servo IC #1 should abide by the following rule: PWM_Frequency_recipient = (n/2)*Phase_Frequency_Generator where n is an integer. - You can use the Delta Tau Calculator for help calculating clock settings. It is posted on the forum: http://forums.deltatau.com/showthread.php?tid=89 So if your Servo IC #0 Phase Clock (generator) is at default of 9KHz, then an acceptable PWM settings for a nice DAC (filtered PWM) output is 27 KHz (where n =6). Example: // 27KHz PWM, 9KHz Phase, 2.25 KHz Servo I7100=1090 I7101=5 I7102=3 // Output Mode , PWM I7126=0 ; default // Maximum Output I669=1090 ; DAC limit 10 Vdc if I600=1 (motor active), you can issue open loop commands proportional to the maximum output. A #6O50 should show +5Vdc. If I600=0 (motor not active), you can write directly to the command output register using suggested M variable Mxx02. M602=545 should show +5vdc.