3.2 Operation Check Using Logging/Trace Monitor3-73.2.4 Checking Logging Speed (When Selecting Logging For Application)• When the logging speed to the buffer memory of the control unit is faster than the writingspeed into an SD memory card, the logging over-speed relay turns on. The logging over-speed relay turns on at the timing of logging trigger, and turns off if the speed does notexceed at the end of scan.• If overspeed occurs frequently, the buffer memory will be full and data cannot beaccumulated.• Once the buffer memory is full, the buffer overflow flag turns on, and the buffer overflowcounter is incremented by one.• If the buffer overflow occurs continuously, revise the logging conditions to decrease thelogging speed.• To know how much logging data was lost at the time of buffer overflow, register the bufferoverflow counter as logging data.• Even if the buffer overflow occurs, recording data into an SD memory card goes on, andlogging continues when free space becomes available in the buffer.• The free space of buffer memory can be checked with the system data registers DT90600 toDT90603.• The system relays (R9184/R9194/R9204/R9214) give a warning when the buffer memory ofeach LOG number is full.
