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.


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.