A 115 V dc generator delivers 120 A to a load. If the generator has an efficiency of 81 percent, calculate the mechanical power needed to drive it [hp].

A machine having class B insulation attains a temperature of 208°C (by resistance) in a torrid ambient temperature of 180°C. a. What is the temperature rise? b. Is the machine running too hot and, if so, by how much?

1 Name the losses in a dc motor. 2 What causes iron losses and how can they be reduced? -3 Explain why the temperature of a machine increases as the load increases.

20. A tractor weighing 14 kN with a wheel base of 3m carries an 8 kN load on its rear wheel. Compute the maximum bending moment and shear when crossing a 4.5 span. Consider the load only at the wheels.

A 110-V, three-phase, Y-connected, 8 pole, 48-slot, 6000-rpm, double-layer wound chronoun anı vonorotor boo 10 +1 urn or oil

-7 Name some of the factors that contribute to the deterioration of organic insulators. -8 A motor is built with class H insulation. What maximum hot-spot temperature can it withstand?

Calculate the full-load current of a 250 hp, 230 V dc motor having an efficiency of 92 percent.

Assignment #2 A 110-V, three-phase, Y-connected, 8 pole, 48-slot, 6000-rpm, double-layer wound, synchronous generator has 12 turns per coil. If one side of the coil is in slot 1, the other side is in slot 6. There are 4 parallel paths. When the generator delivers the rated load at a line voltage of 110 V, the voltage regulation is 5%. What is the flux per pole? Draw two consecutive phasegroups of one of the phase windings and connect them (a) in series and (b) in parallel showing the Start (S) and Finish (F) of both connections. (A separate drawing for each connection)

3-4 Transmissiva Live of 120km has R= 0.2 ~2/15 X= 0.8 -2/km Y = 15H/6 5/km The line is supplies a load of 45 kV, SOMW, 0.8 lead p.f find sending voltage, Sending Current p.f. Sanding Voltage Regulation ⑨Voltage 5 Ⓒ charching coming! изу usy π cct ले