Yaskawa JAPMC-MC2300 - Manual (Page 155)

7.2 Motion Command Details
7.2.3 Zero Point Return (ZRET)
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7
Motion Commands
7.2.3 Zero Point Return (ZRET)
When the Zero Point Return command (ZRET) is executed, the axis will return to the zero point of the machine coordi-
nate system.
The operation to detect the position of the zero point is different between an absolute encoder and an incremental
encoder.
With an absolute encoder, positioning is performed to the zero point of the machine coordinate system, the machine
coordinate system is constructed using the zero point as the value set for OL
48 (Zero Point Position in Machine
Coordinate System Offset), and then the command execution is completed.
When using an absolute encoder, use POSING (positioning) command instead of ZRET (zero point return) com-
mand unless ZRET command is absolutely necessary.
With an incremental encoder, there are 17 different methods (see below) that can be performed for the zero point return
operation.
( 1 ) Selecting the Zero Point Return Method (with an Incremental Encoder)
When an incremental encoder is selected for the Encoder Selection by fixed parameter No. 30 to 0, the coordinate sys-
tem data will be lost when the power supply is turned OFF. This command must be executed when the power supply is
turned ON again to establish a new coordinate system.
The following table lists the 17 zero point return methods that are supported by the MP2000 Series Machine Controller.
Select the best method for the machine according to the setting parameters. Refer to the page in the Table for additional
command information.
Setting
Parameter
OW 3C
Name Method Signal Meaning
Reference
Page
0 DEC1 + Phase-C
Applies a 3-step deceleration method
using the deceleration limit switch and
phase-C pulse.
DEC1 signal: DI_5 or OW 05, bit 8 7-21
1 ZERO signal Uses the ZERO signal. ZERO signal: DI_2 7-22
2
DEC1 + ZERO
signals
Applies a 3-step deceleration method
using the deceleration limit switch and
ZERO signal.
DEC1 signal: DI_5 or OW 05, bit 8
ZERO signal: DI_2
7-23
3 Phase-C Uses the phase-C pulse. − 7-24
4
DEC2 + ZERO
signals
Uses the deceleration limit switch (LS)
signal as the zone signal, and ZERO
signal as the zero point signal.
DEC2 signal: DI_5 or OW 05, bit 8
ZERO signal: DI_2
7-25
5
DEC1 + LMT +
ZERO signals
Uses the deceleration limit switch (LS)
signal and two limit signals (LMT) for
zero point return as the zone signals, and
ZERO signal as the zero point signal. DEC1 signal: DI_5 or OW 05, bit 8
Reverse LMT signal: OW 05, bit 9
Forward LMT signal: OW 05, bit 10
ZERO signal: DI_2
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6
DEC2 + Phase-C
signals
Uses the deceleration limit switch (LS)
signal as the zone signal, and the phase-
C signal as the zero point signal.
DEC2 signal: DI_5 or OW 05, bit 8 7-34
7
DEC1 + LMT +
Phase-C signals
Uses the deceleration limit switch (LS)
signal and two limit signals (LMT) for
zero point return as the zone signals, and
the phase-C signal as the zero point
signal.
DEC1 signal: DI_5 or OW 05, bit 8
Reverse LMT signal: OW 05, bit 9
Forward LMT signal: OW 05, bit 10
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11 C pulse Only Uses only the phase-C pulse.
P-OT: DI_3
N-OT: DI_4
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12 P-OT & C pulse
Uses the positive overtravel signal and
phase-C pulse.
P-OT: DI_3 7-44
13 P-OT Only Uses only the positive overtravel signal.
P-OT: DI_3
This method must not be used if repeat
accuracy is required.
7-45
14 Home LS & C pulse Uses the home signal and phase-C pulse.
P-OT: DI_3, N-OT: DI_4
HOME: DI_2
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15 Home LS Only Uses only the home signal.
P-OT: DI_3, N-OT: DI_4
HOME: DI_2
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