Mitsubishi Electronics FX3G User Manual

210

/FX

3GC

/FX

3UC

Series

Programming Manual - Basic & Applied Instruction Edition

7 Basic Instruction

7.11 MEP, MEF

Caution

1. MEP and MEF instructions may not operate normally if the indexed contact is modified and

changed to pulses by sub-routine programs, the FOR and NEXT instructions, etc.

2. As the MEP and MEF instructions operate using the operation results immediately before them,

use at the list program as the AND instruction.
The MEP and MEF instructions cannot be used at the list program as LD or OR.

3. When programmed in a branch, the MEP/MEF instruction judges the rising/falling edge based on

the rung status up to just before the MEP/MEF instruction in the branch.

4. Caution on writing during RUN

1) Pulse command during rising edge of operation (MEP instruction) results

After writing to the circuit with MEP instructions during RUN, the MEP instruction result turns ON (conductive)
while the operation results up to the MEP instruction are ON.

2) Pulse instruction during falling edge of operation (MEF command) results

After writing to the circuit with MEF instructions during RUN , the MEF instruction result turns OFF (non-
conductive), regardless of the operation results up to the MEF instruction. The operation results of MEF
instruction turns ON (conductive) when the operation results up to the MEF instruction turn OFF.

Error

• There are no calculation errors in the MEP and MEF instructions.

Operation Results up to MEP/MEF Instruction

(while writing is executed during RUN)

MEP Instruction

MEF Instruction

OFF

OFF (non-conductive)

ON (conductive)

OFF (non-conductive)

Circuit program

List program

LD
LD
MEP
OR

0
1
2
3

Y001

SET

M0
M1

SET

Y001

ANB

Judges the rising/falling edge based on the rung status in this range.