Chapter 2 Devices 2-35 Special auxiliary relay Refresh time SM8 The system automatically sets SM8 to ON and resets it to OFF. SM8 is automatically set to ON when there is a watchdog timer error. SM9 The system automatically sets SM9 to ON and resets it to OFF. SM9 is automatically set to ON when there is a system error. SM10 The system automatically sets SM10 to ON and resets it to OFF. SM10 is automatically set to ON when there is an I/O bus error. SM22, SM23, and SM24 Users set the flag to ON, and the system automatically resets it to OFF. The log is cleared when the flag is ON. SM25~SM26 The system automatically sets the flag to ON and resets it to OFF.
The flag is refreshed every scan cycle. SM96~SM97 Users set the flag to ON. After the data is sent, the system automatically resets the flag to OFF. SM98~SM99 The system automatically sets the flag to ON and resets it to OFF. The flag is automatically set to ON when the command is sent. SM100~SM101 The system automatically sets the flag to ON, and users reset it to OFF. The flag is set to ON when the command is received. SM102~SM103 The system automatically sets the flag to ON, and users reset it to OFF. The flag is automatically set to ON when the command received is wrong. SM104~SM105 The system automatically sets the flag to ON, and users reset it to OFF.
The flag is set to ON when there is a receive timeout. SM106~SM107 Users set the flag to ON and reset it to OFF. ON: The 8-bit mode OFF: The 16-bit mode SM204~SM205 Users set the flag to ON, and the system automatically resets it to OFF. ON: Clearing the non-latched/latched areas SM206 Users set SM206 to ON and reset it to OFF. ON: Inhibiting all output SM209 Users set SM209 to ON, and the system automatically resets it to OFF. ON: The communication protocol of COM1 changes. SM210 Users set SM210 to ON and reset it to OFF. ON: The RTU mode SM211 Users set SM211 to ON, and the system automatically resets it to OFF. ON: The communication protocol of COM2 changes.
SM212 Users set SM212 to ON and reset it to OFF. ON: The RTU mode SM215 Users set SM215 to ON and reset it to OFF. ON: The PLC runs. SM220 Users set SM220 to ON and reset it to OFF. ON: Calibrating the real-time clock within ±30 seconds SM400~SM401 The system automatically sets the flag to ON and resets it to OFF. The flag is refreshed every scan cycle. SM402~SM403 The system automatically sets the flag to ON and resets it to OFF. The flag is refreshed whenever the instruction END is executed. SM404 The system automatically sets the flag to ON and resets it to OFF. SM404 is refreshed every 5 milliseconds. SM405 The system automatically sets SM405 to ON and resets it to OFF.
SM405 is refreshed every 50 milliseconds. SM406 The system automatically sets SM406 to ON and resets it to OFF. SM406 is refreshed every 100 milliseconds. SM407 The system automatically sets SM407 to ON and resets it to OFF. SM407 is refreshed every 500 seconds.