Mitsubishi Electric FX3U SERIES - Page 159

FX 3S /FX 3G /FX 3GC /FX 3U /FX 3UC PLC User's Manual - Positioning Control Edition
Built-in Positioning Functions
6 Mechanical Zero Return - DSZR/ZRN Instruction
6.3 Zero Return (ZRN Instruction)
B - 115
A
Common Items
B
Built-in Positioning Functions
Apx.
Example Connection
1. Zero return operation
Zero return operation is described below assuming that Y000 is specified as the pulse output destination
device . If Y001, Y002, and Y003 are specified, it is necessary to change the output number of each
related relay (special auxiliary relay, special data register) below.
 For details on related flags, refer to Section 4.1 to Section 4.4, or Subsection 6.2.2.
1) Execute the ZRN instruction to carry out zero return.
2) Transfer operation will be performed at the zero return speed specified by .
3) If the near-point signal (DOG) specified by is turned on, the speed will be reduced to the creep
speed specified by .
4) If the near-point signal (DOG) specified by is turned off, the pulse outputting operation will be
immediately stopped.
5) If the CLEAR signal output function (M8341) is enabled (set to ON), the CLEAR signal (Y004) will be
turned on within 1 ms
*1
after the near-point signal (DOG) is turns from ON to OFF, and will be kept ON for
"20 ms + 1 scan time (ms)".
*2
6) The current value register (D8341, D8340) will be reset to "0" (will be cleared).
7) "Instruction execution complete" flag will be turned on, and the zero return operation will be completed.
For details on "Instruction execution complete" flag, refer to Subsection 4.7.4.
*1. Within 1 ms when an input X000 to X007 (X000 to X005 in the FX
3S PLC) is used for the near-point
signal (DOG), and within “1 ms + 1 scan time” when an input X010 or later (X006 or later in the FX
3S
PLC) is used for the near-point signal (DOG).
*2. FX
3S/FX3G/FX3GC PLCs operate in the sequence "CLEAR signal output  Pulse output stop".
Set the CLEAR signal detection to "While on, droop pulses are always cleared" for connected
amplifiers (drivers).
The stop position may deviate if it is set to "Droop pulses are cleared on the leading edge".
D
S
1
S
3
S
2
S
3
Maximum speed
(D8344,D8343)
Zero return speed
Deceleration
time
(D8349)
Bias speed
(D8342)
Acceleration
time
(D8348)
DOG
Creep speed
CLEAR signal
Y004
Front endRear end
*1*2
20 ms + 1scan time (ms)
S2
ON
"Instruction
execution
complete" flag
M8029
When the instruction is turned off, M8029 is turned off.
S1
S3
Downloaded from ManualsNet.com search engine