
4. REFERENCE POSITION ESTABLISHMENT
B–63523EN–1/03
588
Parameter
No.1821 (Mark1 interval) = ”20000”
No.1882 (Mark2 interval) = ”20020”
No.1883 (Reference position) = Position of point A + 5.000
= (Distance of A to B) / ( Mark2 interval – Mark1 interval)
* Mark1 interval + 5.000
= 9960 / (20020–20000) * 20000 + 5000
= 9965000
”–9965000”(Reference point is located in minus side)
[The setting method of parameter No.1883]
(Linear scale with absolute addressing reference mark (A/B phase))
When the measurement of a parameter No.1883 (Distance between scale
zero and reference position) is difficult, you can determine the setting
value by the following procedure.
(1)Set ”1” to parameter No.1815#2,#1 to make this function available.
Set a correct value to parameter No.1821, No.1882.
Set ”0” to parameter No.1240.
Set ”0” to parameter No.1883,1884.
(2)Establish a reference point by the procedure described in ”1.2.1
Procedure for Reference Position Establishment”. (As a result, the
machine coordinate becomes the distance between scale zero and
actual position.)
(3)Positioning the axis to reference position by mechanical measurement
in ”HND” or ”JOG” mode.
(4)Set an actual machine coordinate value (DGN.301) to the parameter
No.1883 after conversion of least command increment to detection
unit. (Multiply DGN.301 and CMR)
(5)Set a parameter No.1240 if necessary.
NOTE
When the setting value is greater than 99,999,999, this
method can’t be used.
[The setting method of parameter No.1883]
(Linear scale with distance–coded reference marks (serial))
Set a positive value when the reference position is located in the +
direction when viewed from the reference point or a negative value when
it is located in the – direction. The following shows the setting procedure:
(1)Set bits 1 (OPTx) and 2 (DCLx) of parameter No. 1815 and bit 3
(SDCx) of parameter No. 1818 to enable this function.
Set ”0” to parameter No.1240.
Set ”0” to parameter No.1883,1884.
(2)Establish a reference point by the procedure described in ”1.3.1
Procedure for Reference Position Establishment”. (As a result, the
machine coordinate becomes the distance between datum point and
actual position.)
(3)Positioning the axis to reference position by mechanical measurement
in ”HND” or ”JOG” mode.