Data in the buffer is lost if power fails before writing to SD. Use an HMI model with a or connect the HMI to a small UPS. Alternatively, trigger a "Data Flush" macro on a power-down event (using a PLC power-fail bit).
The HMI reads values from specified PLC registers or internal memory addresses. delta hmi data logging
Let's set up a practical example: Logging a temperature (PLC register D0) and a production count (D10) every 30 seconds to an SD card. Data in the buffer is lost if power
: Good for short-term data displayed on the screen . USB Disk/SD Card : delta hmi data logging
Delta recommends industrial-grade SD cards (e.g., Swissbit, Transcend Industrial). Consumer cards may fail in high-vibration or high-temperature industrial environments.