Electric controlled machine T4/T5 is the latest generation of operational structure for breaker with plastic shell,whose advantages include smaller cubage,longer lifespan(upto 20,000 cycles) and reliable motion etc.It could be operated both by manual and automatically by electric motion and could be locked by hand.Electric controlled machine has direct mechanical display and remote indication by electronic signals.It could be controlled remotely or by intelligent PC and could achieve electric interlocking applied together with breaker with optional protection,whose operation is wecure and reliable.