READ PART COUNTERS | HEIDENHAIN

For any kind of performance-, OEE- or cycle-related analysis of machine data information about the number of produced workpieces is necessary. For machines equipped with Heidenhain TNC and iTNC controllers CNCnetPDM enables to automatically acquire part counter data without any user action required at the machine.

TECHNICAL BACKGROUND | ACQUIRE PART COUNTS | READ COUNTER DATA

FIG 1:    Part counter output (Heidenhain TNC 640)

TECHNICAL BACKGROUND

Heidenhain controllers have the ability to display and store workpiece counters. Storage is performed by the machine’s Programmable Logic Controller (PLC). For legacy TNC 426, 430 and iTNC 530 devices PLC Word Address 20 is used. Older TNC 320 -> TNC 640 devices may use PLC Word Address 10.

Newer controllers (TNC 320 -> TNC 7) use the concept of symbolic PLC address names. Means in practice that the same symbolic name for workpiece counter e.g. DG_PRODUCED_WORKPIECES points to different numeric PLC addresses on every machine.

FIG 2:    Heidenhain PLC workpiece counter (older TNC 640)

ACQUIRE PART COUNTS

For newer controllers (TNC 320 -> TNC 7) you should use the following small NC program to increase the respective PLC address by 1:

0  BEGIN PGM COUNTPART MM 
1  FUNCTION COUNT INC ;Increase workpiece counter by 1
3  END PGM COUNTPART MM 

FIG 3:    Heidenhain part counter NC Program (TNC 640)

By using an NC program you can also directly write to a specific PLC address. To do so you can utilize an unused Q-Parameter that is not reset automatically, preferably between Q20 and Q99. The following example uses Q48. Write a small utility program, here COUNTPART, that maintains parameter Q48 and updates the respective PLC Address value.

• Note: Please select only one version of line 2 according to your controller type.

0  BEGIN PGM COUNTPART MM 
1  FN 1: Q48 =+Q48 + +1 ;Increase Q48 by 1
2  FN 17: SYSWRITE ID 2000 NR70 IDX20 =+Q48 ; Write Q48 to PLC Workpiece Counter W20 iTNC 530
2  FN 17: SYSWRITE ID 2000 NR70 IDX10 =+Q48 ; Write Q48 to PLC Workpiece Counter W10 TNC 640
3  END PGM COUNTPART MM 

FIG 4:    Heidenhain part counter NC Program

To count parts you simply have to add one line to every NC Program before its end that calls program COUNTPART e.g.

...
10  CALL PGM COUNTPART
11  END PGM FELGE_MILL MM

FIG 5:    Call Heidenhain part counter NC Program COUNTPART

READ COUNTER DATA

Reading of part counts with CNCnetPDM can be controlled by using the INI file of the machine which is automatically created for every connected device e.g. heidenhain_1000.ini for machine number 1000. For counting workpieces section [1] of this file is used.

• To activate counting edit the file with a text editor and set Command = plcword and Active = 1.
• For TNC 426, 430 and iTNC 530 set Input parameter 1 to 20.
• For older TNC 320 to TNC 640 controls set Input parameter 1 to 10.
• Make sure that CollectCounters = 1 is set in CNCnetPDM.ini.

[1]
Active = 1
Name = PARTC
Comment = Workpiece counter
Command = plcword
; TNC 426 -> iTNC 530
Input parameter 1 = 20
; TNC 320 -> TNC 640
; Input parameter 1 = 10
Input parameter 2 = 1
Output item = 
Output section = 0

FIG 6:    Activate acquisition of Heidenhain part counters (iTNC 530 & older TNC 320 -> TNC 640)

[1]
Active = 1
Name = PARTC
Comment = Workpiece counter (TNC 640)
Command = plcsymname
Input parameter 1 = STG_WORKPIECE_COUNTER[0].DG_PRODUCED_WORKPIECES
Input parameter 2 = 1
Output item = 
Output section = 0

FIG 7:    Activate acquisition of Heidenhain part counters (newer TNC 320 -> TNC 7)

• To avoid issues please use the Heidenhain PLC utility program to query the respective addresses and compare it with the part counter value shown at the operator panel (ST:x).