Problem 517: Two identical shunt generators running in parallel supply a total load current of 2500 A. Each machine has a field resistance of 50 ohms and an armature resistance of 0.01 ohm. The induced emfs generated are 230 and 235 volts, respectively. Calculate the common operating voltage of each machine.
A220 V
B222 V
C223 V
D218 V
#42
Problem 518: Three shunt generators operating in parallel supply a total load current of 2000 amperes. Each machine has a field resistance of 40 ohms and an armature resistance of 0.02 ohm. The emfs generated are 240, 242 and 245 volts respectively. Determine current delivered by each generator.
A550 A, 600 A, 850 A
B550 A, 650 A, 800 A
C500 A, 650 A, 850 A
D600 A, 600 A, 800 A
#43
Problem 519: Two shunt generators running in parallel deliver a total current of 3,600 A. Each machine has a field resistance of 60 ohms and an armature resistance of 0.01 ohm. The emfs generated by each machine are 455 and 460 V, respectively. Calculate the kW share of each machine.
A652 kW, 1087 kW
B670 kW, 1069 kW
C641 kW, 1098 kW
D682 kW, 1057 kW
#44
Problem 520: A shunt generator and a battery are connected in parallel serving a 500 A busload. The generator has an external characteristics such that the terminal voltage drops uniformly from 460 volts on no load to 440 volts on rated load while delivering 125 A of current. The battery has an open circuit emf is 420 V and internal resistance of 0.01 ohm. What percentage of the load current does the battery deliver?
A53 %
B47 %
C64 %
D36 %
#45
Problem 521: A 50 kW, 220 V dc generator has a voltage regulation of 10%. It is connected in parallel with a battery of 115 cells, each with an emf of 2 V and internal resistance of 0.01 ohm. What current will the battery carry if by accident the load is trip-off from the bus.
A0 A
B8.02 A
C6.15 A
D7.20 A
#46
Problem 522: Two identical 600 kW, 230 V dc generators are operating in parallel and take equal shares of an 800 kW, 250 V busload. The voltage regulation of each machine is 5%. If one of the generators is accidentally tripped off from the line, what is the voltage of the remaining machine?
A250 V
B243 V
C245 V
D247 V
#47
Problem 523: Two 250 V DC generators are operating in parallel and taking equal shares of a 3000 A, 250 V bus load. Ratings: Generator 1 (2% reg, 500 kW), Generator 2 (4% reg, 400 kW). If the load drops to 2100 A, determine the new operating bus voltage.
A252 V
B256 V
C254 V
D253 V
#48
Problem 524: Two shunt generators are operating in parallel and taking equal shares of a 2400 A, 230 V bus load. Ratings: Generator 1 (3% reg, 500 kW, 250V), Generator 2 (4% reg, 600 kW, 250V). If an additional 600-A load is connected to the bus, determine the current delivered by each generator at this condition.
