Various Special Relays For Operation Commands; Forward Rotation Limit And Reverse Rotation Limit - Mitsubishi Electric Melsec-F FX3GC Series User Manual

FX /FX /FX /FX /FX
3S 3G 3GC 3U 3UC
Built-in Positioning Functions
4.3

Various Special Relays for Operation Commands

4.3.1

Forward Rotation Limit and Reverse Rotation Limit

When using the servo motor, the forward rotation limit and the reverse rotation limit can be set for the servo
amplifier.
To use the DOG search function for zero return, or to set the forward rotation limit or the reverse rotation limit
for operations other than zero return using the PLC, set the forward rotation limit 1 (LSF) and reverse rotation
limit 1 (LSR) for the PLC so that these limit switches can be activated before the forward rotation limit 2 or
reverse rotation limit 2 of the servo amplifier.
As shown in the following figure, interlock the forward rotation limit 1 (LSF) with the forward limit relay, and the
reverse rotation limit 1 (LSR) with the reverse limit relay. If the forward limit relay or the reverse limit relay turns
ON, the motor will perform operation depending on the output instruction as shown in the following table.
Reverse rotation limit 2
(Servo amplifier side)
Servo motor
Forward rotation limit 1
Reverse rotation limit 1
Use the relays shown in the following table to determine the forward rotation limit and the reverse rotation limit
for each pulse output destination device (Y000, Y001, Y002, Y003).
Pulse output
Forward limit
destination
device
Y000
Y001
*1
Y002
*2
Y003
*1. Y002 is not available in FX
*2. Y003 is available only when two high-speed output special adapters are connected to the FX
*3. M8338 is supported in the FX
PLC is used and its version is below Ver. 2.20, the PLSV instruction will perform operation in the
M8338 = OFF mode (will perform operation without acceleration/deceleration).
*4. Only available for FX
Note:
If the forward rotation limit (LSF) and the reverse rotation limit (LSR) cannot be set, observe the following
items:
• Even if forward rotation limit 2 or reverse rotation limit 2 turns ON and the servo motor is automatically
stopped, the positioning instruction currently being activated cannot recognize the motor being stopped.
Therefore, pulses will be continuously output until the instruction is deactivated.
• The DOG search function of the DSZR instruction (zero return instruction with DOG search function)
cannot be used.
PLC User's Manual - Positioning Control Edition
Reverse rotation limit 1
(Programmable
controller side)
LSR
Reverse rotation
M8343
Forward limit relay for Y000
M8344
Reverse limit relay for Y000
Reverse limit
relay relay
M8343 M8344
M8353 M8354
M8363 M8364
M8373 M8374
PLC (14-point and 24-point type) and FX
3G
PLC Ver. 2.20 or later and FX
3UC
and FX PLCs.
3U 3UC
4.3 Various Special Relays for Operation Commands
Forward rotation limit 1 Forward rotation limit 2
(Programmable (Servo amplifier side)
controller side)
LSF
Forward rotation
Corresponding instruction and stop
PLSV instruction
*3
(M8338 =OFF)
If the corresponding rotation
the
limit relay is turned on,
pulse output (operation) will
immediately stop.
/FX
3S
4 Before Programming
*4
DSZR, DVIT , ZRN,
*3
PLSV(M8338 =ON), DRVI,
and DRVA instructions
If the corresponding rotation
limit relay is turned on, the
speed will decelerate, and
operation will stop.
/FX PLC.
3S 3GC
PLC.
3U
/FX /FX PLC. If an FX
3G 3GC 3U
B - 57
A
B
Apx.
the
3UC