Specifications

PSU - 10 Positioning Drive Setup Ver. 0002

PSU.5.2 LINEAR FEEDBACK WITH DISTANCE-CODED REFERENCE

MARKS

A slight movement of the motor is enough for the Drive to identify the absolute position of the

machine.

To carry out this procedure, the feedback device must be identified using the following

parameters.

NP117 -S117- ResolutionOfFeedback2

NP118 -S118- ResolutionOfLinearFeedback

NP165 -S165- DistanceCodedReferenceMarksA

NP166 -S166- DistanceCodedReferenceMarksB

For example, Fagor steel tape scales have several reference marks separated 100 signal

cycles, the group of marks alternating with the previous ones are separated 100.1 signal

cycles and their resolution is 10 microns.

Let us suppose that in this particular scale model and using a multiplying factor of x10, an

accuracy of 1 micron is obtained. The values to be assigned to these parameters are:

S117 = 20 microns S118 = 2 microns

S165 = 1001 S166 = 1000

To operate with this type of feedback, set the following bits:

5, 3, 1 and 0 of PP115. Proceed as follows:

• PP115 (bit 0) = 1

• PP115 (bit 1) = 1

• move the axis in the direction to be set as positive; if the position coordinate

decreases, invert the value of PP115 (bit 3).

• Do a home search, move the axis in the positive direction and do a home search

again, if the coordinate given after the second home search is smaller than the one

given in the first one, invert the value of PP115 (bit 5).

S166

S165S165

S165

S165 > S166

S117

S166