Selecting the HANDLE mode, you are transferring all manual motions from the control panel to the device that is an integral part of all CNC machines - the handle.

      Fanuc calls this manual device Manual Pulse Generator (MPG), but nobody else does - it is a handle, plain and simple. Most handles are manual devices, but many new models are digital, at least in the sense that they include a small screen display that can show much more then position only.

      Regardless of the design, the handle is a device used for manual axis motion, commonly used in setup. Its design usually includes a coiled cable that can be extended into the working area. During setup, you select the axis you want to move and the amount of increment, then use the wheel to move by a very precise distance. The handle can be set in such a way that the minimum increment (that is the smallest amount of motion) is:

       ▪0.001 mm

       or

       ▪0.0001 inches

      These amounts are standard on all CNC machining centers and CNC lathes. Because of the many features the handle offers, a separate chapter has been developed for that purpose - see chapter named Setup Handle.

       JOG Mode Selection

      The word jog means nothing more than continuous feed. This mode (and the following Rapid mode) have no relation to any program features. Both are strictly used in manual mode, particularly during part setup.

       RAPID Mode Selection

      Rapid mode is logically related to the Jog mode and located next to it. While JOG mode is used for motions that require manual feedrate, the RAPID mode is used in manual operations to provide rapid motion of the selected axis.

      In conjunction with the axis selection and direction of motion, any single axis can be moved in two directions. Velocity of the rapid motion will also depend on the setting of the Rapid Override Switch (described later).

      For safety reasons, the rapid motion will only take place, while the ± switch is being pressed.

       During setup, it is safer to start with medium or slow rapid motion and increase it as necessary

       MDI Mode Selection

      MDI stands for Manual Data Input. This feature enables the CNC operator to enter one or more program blocks as a group and process them together. MDI mode is for temporary use only, for example, during setup or testing. It is not intended to run production programs.

      MDI mode can be called programming on the fly - if you want to use this mode, you have to have at least rudimentary knowledge of programming. MDI mode uses actual program codes to achieve certain results.

      For example, the following MDI command will move the X-axis by negative 271.450 mm, in rapid mode:

      G91 G00 X-271.450

      The motion will start at the current tool position and end 271.450 mm away in the negative X direction.

      The process is simple:

       ▪Select the MDI mode

       ▪Type-in the desired command block or series of blocks

       ▪Press Cycle Start button to execute

       Each block must be terminated by the EOB key, which is the End-Of-Block key

       DNC / EXT / REMOTE / TAPE Mode Selection

      Depending on the control unit, this switch selection will be identified by one of the descriptions listed in the title. Regardless of the description, the switch always refers to a certain external mode of operation. Normally, there are two modes of operations:

▪MEMORY	... identified as MEM
▪EXTERNAL	... identified as DNC / EXT / TAPE / REMOTE

      Memory type of program processing is controlled by the MEMORY mode selection (see details in the next section).

      The other external types of operations are all the same - they are just identified by a different label on the operation panel of the control system.

      Abbreviation DNC

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