CSC-101 is selective, reliable and high speed protection IED for transmission line, with powerful capabilities to cover following applications: 1) For 35KV to 1000KV transmission lines, W/O serial compensation equipment, or W/O parallel lines, heavy load line, extreme long line or short line; 2) Support duel CT inputs of multi-breaker arrangement; 3) Fully proven protection functions library; 4) Customized protection function scheme, All in one or main protection unit only; 5) Powerful scalable hardware capability, for present and future application: Mixable CT&VT inputs/SV(Sampling Value) input/output; Mixable Binary inputs & output relays/GOOSE inputs /outputs; 6) Robust hardware with excellent EMC performance and IP54 protection under -40℃ to 70℃ operating temperature.