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mycnc:independent_pulse_generator [2019/10/03 14:31]
ivan
mycnc:independent_pulse_generator [2019/10/04 09:36] (current)
ivan
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 When utilizing the Hardware PLC, you MUST use the "​raw"​ value register entry (8130) and independently take into account the multiplier (in the PLC code), as no such helpful conversion is available. ​ When utilizing the Hardware PLC, you MUST use the "​raw"​ value register entry (8130) and independently take into account the multiplier (in the PLC code), as no such helpful conversion is available. ​
  
-**Independent Pulse Generator Spindle implementation example**+===Independent Pulse Generator Spindle implementation example===
  
 1. Add the code that enables the generator into the Hardware PLC procedure M03.plc (spindle ON procedure). It is convenient to add code to the end of the procedure before the exit(99); line. 1. Add the code that enables the generator into the Hardware PLC procedure M03.plc (spindle ON procedure). It is convenient to add code to the end of the procedure before the exit(99); line.
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   exit (99); // normal exit   exit (99); // normal exit
 </​code>​ </​code>​
 +
 +
 +{{plc:​mycnc-spindle-pulse-dir-001.png}}
 +
 +{{plc:​mycnc-spindle-pulse-dir-002.png}}
 +
 +{{plc:​mycnc-spindle-pulse-dir-003.png}}
  
 In this implementation,​ the pulse-dir generation will be switched ON simultaneously with the classic control (a + 0-10V relay analog output). It is assumed that an unused spindle will be shut off physically by the operator and that the additional control signal will not affect operation. ​ In this implementation,​ the pulse-dir generation will be switched ON simultaneously with the classic control (a + 0-10V relay analog output). It is assumed that an unused spindle will be shut off physically by the operator and that the additional control signal will not affect operation. ​
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 </​code>​ </​code>​
  
-In this example, we are assuming that the speed of a conventional spindle is 24,000 rpm. This value, respectively,​ is registered as the maximum spindle speed in the settings (//Settings > Config > Technology > Mill/Lathe > Spindle//). At this spindle speed, a full 10V signal must be sent to the analog output, so the "​voltage ratio" coefficient is set to "​1"​ (in the case of, for example, a spindle with an input signal range of 0-5V, this coefficient would be 0.5 to get a 5V signal at maximum speed).+In this example, we are assuming that the speed of a conventional spindle is 24,000 rpm. This value, respectively,​ is registered as the maximum spindle speed in the settings (//Settings > Config > Technology > Mill/Lathe > Spindle//​). ​ 
 + 
 +{{plc:​mycnc-spindle-pulse-dir-004.png}} 
 + 
 +At this spindle speed, a full 10V signal must be sent to the analog output, so the "​voltage ratio" coefficient is set to "​1"​ (in the case of, for example, a spindle with an input signal range of 0-5V, this coefficient would be 0.5 to get a 5V signal at maximum speed).
  
-When calling the PLC procedures for turning ON the spindle (M03.plc) and changing the spindle speed (SPN.plc), the spindle speed value is stored in the **eparam** variable.+When calling the PLC procedures for turning ON the spindle (M03.plc) and changing the spindle speed (SPN.plc), the spindle speed value is stored in the **eparam** variable. ​
  
 myCNC controllers have 12-bit registers for PWM and DAC at 0-10V.This means that with a maximum spindle speed of **24000 rpm** and a factor of **1**, the ''​eparam''​ variable will have a maximum value of 4095. myCNC controllers have 12-bit registers for PWM and DAC at 0-10V.This means that with a maximum spindle speed of **24000 rpm** and a factor of **1**, the ''​eparam''​ variable will have a maximum value of 4095.
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 Assume that the maximum servo spindle speed is 4,500 rpm. Then the ''​eparam''​ value at a speed of 4500 rpm will be: Assume that the maximum servo spindle speed is 4,500 rpm. Then the ''​eparam''​ value at a speed of 4500 rpm will be:
  
-<​code>​ 4500 * (4095/24000) = 768</​code>​+<​code>​ 4500 * (4095 ÷ 24000) = 768</​code>​
  
 The Pulse-Dir input of the servo spindle is set to 10,000 pulses, i.e. the motor shaft will make a full revolution every 10,000 pulses. Then, to achieve a full speed of 4500 rpm, the following pulse rate is required: The Pulse-Dir input of the servo spindle is set to 10,000 pulses, i.e. the motor shaft will make a full revolution every 10,000 pulses. Then, to achieve a full speed of 4500 rpm, the following pulse rate is required:
  
-<​code>​10000 * (4500/60) = 750 000</​code>​+<​code>​10000 * (4500 ÷ 60) = 750 000</​code>​
  
-The register RAW value for 750kHz (750,​000Hz) ​should ​be+The register RAW value for 750kHz (750,​000Hz) ​will therefore ​be calculated as follows:
  
-<​code>​ 750000 ​0.0014549 = 515499347</​code>​+<​code>​ 750000 ​÷  ​0.0014549 = 515499347</​code>​
  
-If the maximum speed corresponds to the ''​eparam''​ value of "​768",​ then the value of the coefficient to obtain "​515499347"​ will be+If the maximum speed corresponds to the ''​eparam''​ value of "​768",​ then the value of the coefficient to obtain "​515499347"​ will be calculated as follows:
  
-<​code>​ 515499347/768 = 671223</​code>​+<​code>​ 515499347 ​÷ 768 = 671223</​code>​
  
 By setting these values ​​in the M03.plc and SPN.plc procedures, we will generate the required 750 kHz frequency when the spindle speed is set to 4500, as well as smooth frequency control over the entire range from 0 to 4500 rpm. By setting these values ​​in the M03.plc and SPN.plc procedures, we will generate the required 750 kHz frequency when the spindle speed is set to 4500, as well as smooth frequency control over the entire range from 0 to 4500 rpm.
  
  
-**A method for evaluating the required acceleration of a generator**+===A method for evaluating the required acceleration of a generator===
  
 One unit of the generator acceleration is, by a very rough approximation,​ 1 impulse / s2. This means that with such an acceleration,​ the generator “accelerates” ​ to a frequency of 1 Hz in 1 second. If, in our case, the maximum frequency is 750,000, then the acceleration must be equal to the same value in order to “accelerate” to this frequency in 1 second. One unit of the generator acceleration is, by a very rough approximation,​ 1 impulse / s2. This means that with such an acceleration,​ the generator “accelerates” ​ to a frequency of 1 Hz in 1 second. If, in our case, the maximum frequency is 750,000, then the acceleration must be equal to the same value in order to “accelerate” to this frequency in 1 second.
  
-**Test code for spindle start-up and spindle speed adjustment procedures**:+===Test code for spindle start-up and spindle speed adjustment procedures===
  
 <code C M03.plc> <code C M03.plc>
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-  //delay after spindle ​started+  //delay after the spindle ​was turned on
   timer=spindle_on_delay;​   timer=spindle_on_delay;​
-  do{timer--;​}while (timer>​0);​ //​delay ​for Spindle reach given speed+  do{timer--;​}while (timer>​0);​ //​delay ​until the spindle reaches the given speed
  
   exit(99);​ //​normal exit    exit(99);​ //​normal exit 
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 <code C SPN.plc> <code C SPN.plc>
 #include vars.h  ​ #include vars.h  ​
-//set Spindle ​speed control via DAC+//set the Spindle ​Speed through ​DAC
 main() main()
 { {
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   {   {
     k=671223; ​     k=671223; ​
-    freq=val*k; //calculate the RAW frequency+    freq=val*k; //calculate the RAW frequency ​using the multiplier
     if (freq>​515499348) {freq=515499348;​};​     if (freq>​515499348) {freq=515499348;​};​
     gvarset(8130,​freq);​ timer=30;​do{timer--;​}while(timer>​0);​ //30ms delay     gvarset(8130,​freq);​ timer=30;​do{timer--;​}while(timer>​0);​ //30ms delay
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 ==== Low level CNC registers to control independent pulse generator ==== ==== Low level CNC registers to control independent pulse generator ====
  
-This is for records only. Users don't have to utilize these settings which are changed ​by having low-level access to the controller.+This is for records only. Users don't have to utilize these settings which can be altered only by having low-level access to the controller.
  
 ^ Register Name ^ Address ^ Description ^ ^ Register Name ^ Address ^ Description ^
mycnc/independent_pulse_generator.txt · Last modified: 2019/10/04 09:36 by ivan