Abstract: A protection relay for 3-phases induction motors hazard protection purpose has been designed utilizing of type A VR AT Mega 32 fuzzy: logic based micro-controller. Distinguish in between conventional relay-protection whose common use in industries before, this new design is prepare for random unbalance voltage, low and or over voltage, one phase missing voltage, and the influence of temperature to the motor s coil instead of detects low or over voltage only. This protection-relay is also completed with reset and setting facilities to indicate the protection-relay's parameters initial position, lower and upper voltage boundaries, and the maximum upper temperature boundaty is needed are invoke via keypad. Such hazard and overloaded in the electric induction motors due to the influence of the unbalance voltage random event can be avoided. Data analysis of the online simulation and laboratory: running test show that both hardware and software good properly works and well functioning
