AH500 Programming Manual 2. For latched use: If an electric power cut occurs when the PLC is running, the state of the auxiliary relay for latched use will be retained. When the power supply is restored, the state remains the same as that before the power electric cut. 2.2.7 Special Auxiliary Relays Every special auxiliary relay has its specific function. Please do not use the special auxiliary relays which are not defined. The special auxiliary relays and their functions are listed as follows. As to the SM numbers marked “*”, users can refer to the additional remarks on special auxiliary relays/special data registers.
“R” in the attribute column indicates that the special auxiliary relay can read the data, whereas “R/W” in the attribute column indicates that it can read and write the data. In addition, the mark “–” indicates that the status of the special auxiliary relay does not make any change. The mark “#” indicates that the system will be set according to the status of the PLC, and users can read the setting value and refer to the related manual for more information. 2-10 CPU5X0-RS2 CPU5X0-EN OFF STOP RUN SM Function Attribute Default ON RUN STOP SM0 Operation error ○ ○ OFF OFF – R OFF SM1 The operation error is locked.
○ ○ OFF OFF – R OFF SM5 Instruction/Operand inspection error ○ ○ OFF OFF – R OFF *SM8 Watchdog timer error ○ ○ OFF – – R OFF SM9 System error ○ ○ OFF – – R OFF SM10 I/O bus error ○ ○ OFF – – R OFF *SM22 Clearing the error log ○ ○ OFF – – R/W OFF SM23 Clearing the download log ○ ○ OFF – – R/W OFF SM24 Clearing the state-changing log of the PLC ○ ○ OFF – – R/W OFF SM25 The online-editing processing flag is on when the online-editing mode starts. ○ ○ OFF – – R OFF SM26 The debugging mode processing flag is on when the debugging mode starts. ○ ○ OFF – – R OFF *SM96 The data is sent through COM1. ○ ○ OFF OFF – R/W OFF *SM97 The data is sent through COM2.
○ × OFF OFF – R/W OFF *SM98 Waiting to receive the reply through COM1 ○ ○ OFF OFF – R OFF *SM99 Waiting to receive the reply through COM2 ○ × OFF OFF – R OFF *SM100 Reception through COM1 is complete. ○ ○ OFF OFF – R/W OFF *SM101 Reception through COM2 is complete. ○ × OFF OFF – R/W OFF *SM102 An error occurs during the reception of the data through COM1 by using the instruction MODRW or the instruction RS. ○ ○ OFF OFF – R OFF *SM103 An error occurs during the reception of the data through COM2 by using the instruction MODRW or the instruction RS. ○ × OFF OFF – R OFF *SM104 No data is received through COM1 after a specified period of time.
○ ○ OFF OFF – R/W OFF *SM105 No data is received through COM2 after a specified period of time. ○ × OFF OFF – R/W OFF