Mitsubishi Electric Melsec-F FX3GC Series User Manual page 157

FX /FX /FX /FX /FX
3S 3G 3GC 3U 3UC
Built-in Positioning Functions
S
3) For , specify the near-point signal (DOG) input device number (NO contact).
3
Turning on the near-point signal will reduce the speed to the creep speed. Turning off the near-point
signal will complete the zero return operation.
• If an input X000 to X007 (X000 to X005 for FX
signal (DOG), the PLC interruption function will be used to stop the operation. (To output the CLEAR
signal, turn on the "CLEAR signal output function enable" relay.)
Under the following condition, however, operation may be affected by the input filter or the scan time of
the sequence program, and the operation, therefore, may not be stopped exactly at the origin.
- An input number of X010 or higher (or other device (auxiliary relay, etc.)) is specified.
If an input relay X010 or higher (X006 or higher for FX
(DOG), the input filter will be applied.
4) For D , specify a pulse output number in the range of Y000 to Y003.
5) Zero return direction
For this instruction, the zero return direction is set to the reverse rotation direction.
(During zero return operation, the value indicated in the current value register will be decreased.)
To perform zero return in the forward rotation direction, follow the example program below to control the
direction output.
a) Turn on Y (rotational direction signal).
b) Refresh Y output using the REF (FNC 50) instruction.
c) Execute the ZRN instruction (zero return instruction).
d) With the execution completion flag (M8029) of the ZRN instruction (zero return instruction), reset
Y (rotational direction signal).
Example program:
In the program shown below, Y004 is specified as the rotation direction signal output device for Y000.
Command
input
M12
PLC User's Manual - Positioning Control Edition
To use the main unit (transistor output), refer to Section 4.8.
To use a high-speed output special adapter, refer to Section 4.9.
FNC156
DZRN
M8029
M8329
6 Mechanical Zero Return - DSZR/ZRN Instruction
For details, refer to "1. Zero return operation".
PLC) of the main unit is specified for the near-point
3S
PLC) is specified for the near-point signal
3S
For programming details, refer to Section 4.7.
RST M10
RST M11
SET M12
SET Y004
FNC 50
Y000 K8
REFP
S S S Y000
1• 2• 3•
RST Y004
SET M10
RST M12
RST Y004
SET M11
RST M12
6.3 Zero Return (ZRN Instruction)
Turns on (sets) Y004 as the
a)
rotational direction signal of
Y000 (pulse output destination).
Refreshes Y000 to Y007.
b)
c) Executes ZRN instruction.
Resets the rotational direction
d)
signal (Y004) using the instruction
execution complete flag.
Origin data reading completion
flag
Resets the rotational direction
signal (Y004) using the
instruction execution abnormal
end flag.
Abnormal end of zero return
B - 113
A
B
Apx.