Tag Archives: mitsubishi plc programming instructions

What is the difference between the usage of m8004 in fx1n and the usage of m8004 in fx3ga?

How to use M8004 in Mitsubishi plc,

The PLC may report an error when an error occurs in the plc’s instruction. We first enter a correct command: input LD X0.

Connect an output component Y0 to X0. This instruction is correct. In order to learn about the M8004 alarm, we can add another wrong command.

Enter the command returned by a subroutine in the command: SRET, and then press the OK key.

In order to view the status of the M8004, we use the M8004 as a contact in the program to control the output of Y4.

After the program is written, press the Convert button to compile the program, then press the Simulate Test button to simulate the program.

When the program is transferred, you can see that the test window has indicated an error, and the auxiliary relay M8004 has also been activated.

Mitsubishi plc ladder diagram instruction

LD X0
AND X2
LD X1
ORI Y1
ANI X4
ORB
LD X3
ORI X5
ANB
OR X7
OUT Y6

MITSUBISHI FX2N PLC special auxiliary relay

mitsubishi plc special relays include M8000 …M8008  M8011….M8019  M8020….M8029  M8030…M8039   Different functions of different special relays serve MITSUBISHI PLC at the same time. 

here  have some mitsubishi plc special relays example you can see

RUN monitoring M8000, M8001

RUN monitoring (M8000, M8001) which shows the running state of PLC can be used as the driving condition of instructions and the external display of “display in normal operation”

RUN is in ON state when normal, and Y0 leads.

M8001 is in OFF state when RUN is normal.

Initial pulse M8002, M8003

After the start of PLC operation, M8002 is ON in one instant (one operation cycle) and remains OFF in the rest of the time. The read pulse is used as initialization signal in the case of program initialization and writing specified value.
M8003 is OFF only at one instant (one operation cycle) after the start of PLC operation, and the rest of the time is in ON state.

SHAPE \* MERGEFORMAT

Operational error flag auxiliary relay M8067

M8067 performs error detection in operation or RUN when PLC is removed from STOP to RUN. When M8067 is ON, save the smallest address number in D8004, M8004 action.