Choose the correct option from the following statements: 1- ........................................ to leave all healthy circuits intact to ensure continuity of supply. (Sensitivity - Selectivity - Stability) 2- is faults in power systems with more than 80% of the occurring faults is (Temporary Faults- Permanent Faults - none of them) 3- .... is based relays are specifically used to calculate algorithm numerically(Solid state relay - Numerical relay - Electromechanical relay) iv. 4- ............ is the most widely used in over-current relay (Inverse definite minim time - Definite time - none of them) 5- ............ fuse where expulsion gases causes no problem (Vacuum-Expulsion - none of them)

Choose the correct answers for the following questions : 1- Device which receives a signal from the power system and determines whether conditions are "normal" or "abnormal" (measuring function) is d. Voltage Transformer c. Current Transformer b. Relay a- Circuit Breaker 2- A ……………..is an electromechanical device break a circuit automatically under fault condition. d. Voltage Transformer c. Current Transformer b. Relay a- Circuit Breaker 3- Good Protection System Should require: d. All of these. c. Adequacy b. Selectivity & Sensitivity a- Reliability & Speed 4- That which tends to close the contacts of the relay. d. All of these. c. Restrain force b- Restrain torque a- Operating force 5- The value of current or voltage below which a relay opens its contacts and comes to original position d. Non of these. c. Set level b. Drop-out level a. Pick-up level 6- What is the purpose of back up protection? d. To leave no blind spot To guard against c. failure of primary b. To increase the reach a. To increase the speed

In digital relay, relay dependability is the ratio of (Number of correct trips)/(Number of desired trips+Number of incorrect trips) (Number of correct trips)/(Number of desired trips) (Number of correct trips)/(Total number of trips) None of the above

How do protective relays and circuit breakers work together in a power system to ensure efficient and reliable operation, and what key functions do they serve in preventing electrical faults and disruptions?

In digital relays; relay algorithms are stored in:

Relay Logic / Instructions