NCT Group NCT 990T, NCT 100T, NCT 2000T manual Types of Reference Point Return

6.1 Manual Reference Point Return Mode

happened yet, symbol !! can be seen beside the position. In case the reference point has been returned on all axes REF, i.e., the caption indicating lack of reference position is cleared from the general NC state field.

LNote:

By different machine tools return to the reference point may function contrary to the above- mentioned process. It is common, that after displaying the operation mode and pressing START button the jog buttons are to be held down for a short time, after that the process goes on automatically. In this case the process can be stopped by pressing STOP button. For details turn to the machine tool builder for an information material.

Types of Reference Point Return

There may be four types of reference point return. The types are determined by the machine tool builder axis by axis in different parameters, in function of the adapted path measuring system.

1. Reference point setting by return to switch, then standing on zero-pulse

The selected axis runs to the reference point switch at high speed, then stops. It comes off the switch at low speed either in the direction of the running on or in the opposite one, and searches for the first zero-pulse, and registers this position reference point.

2. Reference point return with distance coded measuring system

The selected axis searches for two neighboring zero-pulses at low speed. It detects the absolute position of the axis by measuring the distance between the two zero-pulses.

3. Reference point return on grid

The selected axis searches for the zero-pulse at low speed and registers it as reference point.

4. Floating reference point

By pressing the appropriate jog button no movement is made, but the momentary position of the slide is registered as reference point.

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