The CMLIB 7Sx8 is an interface adapter for connecting SIEMENS protection relays fitted with sensor inputs (e.g. SIPROTEC 7SJ81) to the low level outputs of CMC test sets. CMLIB 7Sx8 converts the low-level output signals of the CMC into differential (balanced) signals. In addition, the adapter also provides the simulated voltage system.

CMLIB 7Sx8 can be used in combination with CMC 356, CMC 353, CMC 256plus, CMC 256-6, and CMC 850 test sets.