
B-64120EN/01 4.DESCRIPTION OF PARAMETERS
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reference position. The distance from the zero point of the encoder to
the reference position is obtained from the following equation:
Distance from the zero point of the encoder to the reference position
=No.1884×100,000,000+No.1883
The zero point of the encoder refers to the point at which mark 1 and
mark 2 match. Normally, this point is a hypothetical point that does
not physically exist on the encoder. (See the figure below.)
If the reference position is located on the positive side when viewed
from the zero point of the encoder, set a positive value. If the
reference position is located on the negative side when viewed from
the zero point of the encoder, set a negative value.
Mark 1 Mark 2 Mark 1 Mark 2
Zero point of encoder
Encoder end
Reference position
……..
Mark 1 = mark 2
41.8
8.242.0
8.0
PRM.1821
PRM.1882
PRM.1884
100,000,000 + PRM.1883
[Example of parameter settings] When an encoder as shown below is used with an IS-B,
millimeter machine:
20.000 19.980 9.940 10.060
9.960
10.040 9.980 10.020
5.000 20.000mm
20.020mm -
9960/
20020-20000
*20000+5000
= -9965000
Mark 1
Mark 2 Mark 1 Mark 2Mark 1
Mark 1 Mark 2 Mark 1
Mark
1
Mark 2
Mark 1 = mark 2
B
A
Zero point of encoder + direction - direction
Reference
position
Parameters
No.1821 (interval of mark 1) = 20000
No.1882 (interval of mark 2) = 20020
No.1883 (reference position) = position of point A + 5.000
= distance between A and B/(mark 2 − mark 1) × mark 1 + 5000
= 9960/(20020-20000) × 20000 + 5000
= 9965000