For facility managers and maintenance technicians, this error is more than just an annoyance. The SD card in a Kaeser Sigma Control unit (typically located in the "Top" section of the controller or cabinet) is responsible for data logging, pressure/flow recording, and firmware storage. A write error means your system is failing to document its operational history, which can lead to compliance issues and difficulty diagnosing intermittent faults.
If you see this error, follow these steps in order to resolve the issue: 1. Check Physical Write Protection kaeser sd card write error top
Remove the card and ensure the slider is pushed toward the metal contacts. If you see this error, follow these steps
Once write protection is off, use the Acknowledge button (the key with the circular arrow symbol) on the controller to clear the message. : If the card has no room for
: If the card has no room for new logs, the "write error" will persist until data is deleted or a new card is used. Why the SD Card is Critical
Industrial SD cards have a limited number of write cycles (Endurance). Kaeser controllers write log data frequently—sometimes every second. After 3–5 years of continuous operation, the memory cells in a standard consumer-grade SD card wear out and become "read-only." This triggers a hardware-level write error.