Siemens NCU 7x0.3 PN Series Manual page 166

Appendix
A.1 Abbreviations
SRAM Static RAM: Static memory (battery-backed)
TCU Thin Client Unit (communication with operator panels)
TS Teleservice
VDE Association of Electrical Engineering, Electronics and Information Technology (Germany)
Full duplex An Ethernet/PROFINET port can simultaneously transmit and receive data.
166
NCU 7x0.3 PN
Manual, 09/2011, 6FC5397-1EP40-0BA0