
4. REFERENCE POSITION ESTABLISHMENT
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(1)In the following case, P/S090 alarm occurs.
(a) The actual interval of reference marks is different from parameter
setting value.
(2)In this procedure, the axis does not stop until three or four reference
marks are detected. If this procedure is started at the position near the
scale end, CNC can not detect three or four reference marks and the
axis does not stop until over travel alarm occurs. Please care to start
at the position that has enough distance from scale end.
Scale end
Reference mark
Start point (Bad)
Start point (Good)
f
d
F
(3)In the following cases, this function does not perform.
(a) Parameter No.1821(mark1 interval) or No.1882(mark2 interval) is
”0”.
(b)The setting value of parameter No.1821 and No.1882 are the same.
(c) Parameter No.1821 value w No.1882 value*2
or No.1882 value w No.1821 value*2
(4)Rotary encoder with absolute address referenced mark (A/B phase)
(a) When the rotary encoder with absolute address referenced mark
(A/B phase) is used, please set a parameter No.1815#3 (DCR) to
”1”.
In case of rotary encoder with absolute address referenced mark
(A/B phase), the marker interval may be different from parameter
setting value. (a–b section of the following figure) When the
reference point return is executed through this section, it is not able
to establish the reference point. Therefore, in case of rotary encoder
with absolute address referenced mark (A/B phase), if the reference
point return is started for B point from A point of below figure, the
reference point is not established yet at B point. The reference point
return is re–started for C point. The reference point return
procedure is finished at C point.
9.64_
9.98_
9.96_
19.66_
20.02_
9.94_
20.00_
A
B
C
b
a
20.02_ 20.02_
20.00_
20.00_
Note