NCT Group NCT 990T User Manual

Page 67

Advertising
background image

6.1

Manual Reference Point Return Mode

67

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.

L

Note:

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.

Advertising
This manual is related to the following products: