In the PLC programming a kind of state relay, what role does he play, when will be used to him
?If the start signal X000 is ON in the step control of the operation. The state S20 is set to ON, and the solenoid valve Y000 for lowering is operated. If the lower limit switch X001 is ON, the state S21 is set to ON, and the solenoid valve Y001 for clamping is operated. If the clamp switch X002 is ON, the state S22 is set to ON. As the action moves, the state automatically returns to its original state. The general purpose state is turned OFF after the power is turned off, and the state of the power failure is maintained, and the ON or OFF state before the power failure can be memorized. Therefore, the operation can be started from the midway process.
Introduction to Status Relay in PLC (Status Device)
????The state relay (S) is a kind of "soft relay" inside the PLC. It is the same as the input relay (X) and the output relay (Y). There are numerous pairs of normally open contacts and normally closed contacts, such as no step Components, can be used as a general auxiliary relay (M). FX series internal total state relay 1000, S0 ~ S9 is mainly used in the state transition diagram (SFC) of the initial state, S10 ~ S19 is mainly used in the state transition diagram (SFC) state back to zero, S20 ~ S499 is mainly used in state transition (SFC) in the middle of the state, S500 ~ S899 and S900 ~ S999 were used to maintain power and signal alarm.
