Output for a Scan at Rising and Falling Edge

Rising Edge and Falling Edge Pulse Output for a Scan: PLS, PLF

When a PLS instruction is executed, object devices operate for one operation cycle after the drive input signal has turned ON.

Likewise, when a PLF instruction is executed, object devices operate for one operation cycle after the drive input signal has turned OFF.

Instruction

Device address

No. of Steps

Flag

M

X

Y

K

L

F

T

C

S

Z

D

@D

Int.

Error

Zero

Carry

PLS

PLF

S

o

-

o

-

o

-

1

-

PLS (Pulse – Rising edge pulse)

Function

-Turns the assigned device ON for one scan when the PLS instruction is turned ON from OFF.

For example, when X00 is turned ON from OFF by PLS instruction, the device “M00” is turned ON only for one scan.

-When the PLS instruction is executed on the device specified as Latch Relay (L) and the power is turned OFF and ON again, the device will output the previous value.

-Though PLC is switched from RUN to STOP and STOP to RUN after the PLS instruction, it will not activate the PLS instruction.

PLF (Pulse Falling – Falling edge pulse)

Function

-Turns the assigned device ON for one scan when the PLF instruction is turned OFF from ON.

For example, when X00 is turned OFF from ON by PLF instruction, the device "M01" is turned ON only for one scan.

-Though PLC is switched from RUN to STOP and STOP to RUN after the PLF instruction, it will not activate the PLF instruction.