DNC OPTION 18 | HEIDENHAIN

Top

For newer Heidenhain machine controllers ‘DNC Option 18’ can be purchased optionally. Without it most of the high level language commands to communicate with the equipment from a remote PC are not available. However, even in this case CNCnetPDM allows reading and writing of data. This article describes all steps to setup data acquisition without DNC option 18 from Heidenhain iTNC 530, 320, 620, 640 and TNC7 controllers.

CHECK OPTION AVAILABILITY | ADJUST CNCNETPDM (iTNC 530) | ADJUST CNCNETPDM (TNC 320 - TNC7) | DISABLE UNSUPPORTED COMMANDS | TIPS

CHECK OPTION AVAILABILITY

If the DNC option is not activated the controller refuses to output most information related to machine status to remote devices. If you get output like the following with HeidenhainData or CNCnetPDM just outputs OEE status 1 or 5 even if everything is setup correctly you should check availability of the option.

FIG 1:    HeidenhainData output without DNC option 18 (Symbolic PLC name definitions loaded)

• Note: To review the activation status simply switch the controller to programming mode, press the [MOD] button and enter code-number SIK. If, under SIK Options, HEIDENHAIN DNC is unchecked the option is not activated:

FIG 2:    Check status of DNC Option 18 at the controller (TNC 640)

ADJUST CNCNETPDM

With CNCnetPDM the required data can be acquired by reading it directly from the machine’s Programmable Logic Controller (PLC). To do so you have to modify the INI file that is automatically created by CNCnetPDM for the respective machine on first startup e.g. heidenhain_1000.ini for equipment number 1000.

iTNC 530 CONTROLS

This and all older types set PLC marker address values to 0 or 1 according to the actual machining mode (manual, automatic…) and program state (running interrupted…). As the addresses have fixed values it is sufficient to change entry ‘Legacy PLC’ from 0 to 1 in section [GENERAL] of the devices INI file. In addition deactivate commands that are only supported with Option 18.

TNC 320, 620, 640 and TNC7 CONTROLS

Although these models also keep track of machining mode and program state in their PLC the numeric address location of the markers is different on every single machine as the machine manufacturer freely assigns them. However, as these controllers use symbolic plc names and the name of the relevant markers is identical between different machines CNCnetPDM is able to automatically read the correct values:

1. Follow the steps to extract symbolic PLC name definitions from your machine.
2. In section [GENERAL] entry 'Symbolic PLC Address Names' of your machine INI file enter the name of the file that contains the extracted information, default: plcdatamarker\PlcDataMarker.txt 
3. To inform CNCnetPDM that no DNC option is available change ‘No DNC Option’ in section [GENERAL] from 0 to 1, make sure that ‘Legacy PLC’ is set to 0.
4. In section [MARKERS] set entry 'PLC Marker Command' to plcsymname.

• All done, CNCnetPDM is now ready to detect correct machine states without DNC Option 18.

DISABLE UNSUPPORTED COMMANDS

For controls without DNC option 18 you have to disable output from all numeric sections [1] - [35] that contain one of the following commands by setting ‘Active’ to 0.

Unsupported Command
ncprogram
error
tool
override
axes
cutter
data

FIG 3:    Commands not supported without DNC option 18

TIPS

• For controllers >= TNC 320 most output of commands that are not supported without DNC option 18 can also be read from the machine’s PLC by using command 'plcsymname'. Examples (Symbolic PLC names):
  SPINDLE[0].DG_RPM = Spindle Speed
  APICHN[0].NN_CHNPROGFEEDMINUTE = Programmed Feed
  APICHN[0].NN_CHNCONTOURFEED = Feed Rate
  APICHN[0].NN_CHNAFCSPINDLELOAD = Spindle Load
  < Global >\NN_DG_TOOL_NUMBER = Actual Tool Number
  
  For details review the technical documentation of the machine or ask your machine manufacturer.