LOG_HANDLING Logging Datasets

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Function Block LOG_HANDLING

General Information
Available as of PLC runtime system V2.3 and above
Included in library LogData_AC500_V23.lib
Type Function Block with historical values

Depending on the selected mode this Function Block is used to

  • directly transfer data messages in IEC60870 format or in generic format from SRAM_FIFOin to the RAM_FIFOout in case of an existing communication.
  • store datasets in IEC60870 format or in generic format in files on flashdisk or SD-card for other use or because a communication line is broken.
  • provide these logged datasets at the RAM_FIFOout output in case of recurring communication with higher priority than the current data traffic or via FTP server of the PLC.
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Depending on the mode the Function Block can have three main working states:

  • State 1: Existing communication (CONNECT) und empty FILE-FIFO: Datasets are written into SRAM_FIFOin (First In First Out), which are either from LOG_IEC60870_INPUT or LOG_GENERIC_INPUT (cannot be mixed), and are transported to RAM_FIFOout (First In First Out). There they are either
    • decoded by LOG_IEC60870_OUTPUT and transmitted or
    • decoded by LOG_GENERIC_OUTPUT and provided on its outputs as real data for further transmission (dependant on the chosen input variant: IEC or generic).
  • State 2: Communication failure (DISCONNECT): Datasets, which were written either by LOG_IEC60870_INPUT or LOG_GENERIC_INPUT (cannot be mixed) into the SRAM_FIFOin, will be transmitted into the FILE-FIFO (First In First Out) and stored.
  • State 3: Write/Read Modes and FTP Modes Datalogging Library

This Function Block realises writing and reading of max. 999 files with max. 65535 datasets in a FIFO principle. Data storage can be either the FLASHDISK of a PM59x (with SafeFAT), or an SDCARD (without SafeFAT). In case of SDCARD it must be ensured that after main power failure, for approximately 3…5 sec the 24 V supply is maintained (input extPower = FALSE), in order to close open files properly.