For full load operation of 60Hz, 380V, 4 pole 30kW induction motor,
the speed is 1746rpm, input current 56.2A power factor 90%.
In no load operation, input current 17.3A, power factor 13.5%.
In full load operation, assume that the mechanical loss is 25% of the total loss and no other losses.

a) Iron loss load efficiency
b) Find a rotor copper loss under full load
c) Iron loss
d) Find a fixed automatic hand under full load
e) Find the proportion of fixed loss, iron loss, rotor copper loss and machine loss in total losses.

answer -
a) 90.1%
b) 953W
c) 714W
d) 801W
e) 24.3%

Which logical network topology requires the use of a token that is passed among the nodes?

• A. Ring

• B. Star

• C. Bus

• D. Mesh

1. What is the difference between Interrupt and polling technique? Which one is preferable

and why?

2: Store two values 0x80 and 0x08 in in file register locations 0x40 and 0x41 respectively.

Subtract content of location 0x41from 0x40 and store the result in register 0x43.

A 50 Hz, four-pole, 480 V, three-phase, wye-connected induction machine
has the following parameters:
R1 = 0.2 R2 = 0.3 Xeq = 12
The motor is loaded by a unidirectional constant-torque load of 40 NM. A
countercurrent braking is performed on the motor. Calculate the following:
a. Motor current before the countercurrent braking
b. Motor current just after the voltage sequence is reversed
C. Current at the moment when the motor stops
d. Moter torque at the condition of part ( b) and (c).
e. Motor current at the new steady state point
F. Motor torque at the new steady state point
g. Motor speed at the new steady-state point

Please help answer the question quickly

1. Using Matlab, Design a Band-Stop Filter (BSF) that removes frequencies from 500Hz to 1000Hz in a signal that is sampled at 10kHz.

• Compare an elliptic filter of order 12 and 6 to an order-12 Yule-Walker filter design
• Plot the magnitude of the two designs on the same plot.

What are the main objectives of boiler controls? Explain each objective in details

Theory about the open and short circuit test about the transformer?

Low-Pass RC Filter.

1. Design a low-pass RC filter that will attenuate the amplitude of a 400 Hz sinusoidal wave by a factor of two. Draw a schematic diagram for your filter, labeling V_in, V_out, and your specific choices for your R and C values.
2. At 400 Hz, does the output signal from your filter lead or lag the input signal? By what phase does it lead or lag?
3. On the same set of axis, sketch V_in and V_out as a function of time for several periods of the wave forms. Assume V_in to be a 400 Hz 10 V peak-to-peak sinusoidal wave. Be sure to label your axes.
4. If we change our input to a 1 kHz sinusoidal signal, by what factor will the amplitude of the output be suppressed compared with the amplitude of the input? What will the phase difference between the input and output signals be?

What are the main internal blocks that a typical FPGA (Field Programmable Gate Arrays) device consists of? Sketch what a Configuration Logic Block (CLB) internal design looks like and explain each key part of this CLB block? Label the input/output signals and logic blocks appropriately.

Introduction, Background of Study and Theory behind Induction type Instruments

Sketch the asymptotes of the Bode plot magnitude and phase for the transfer functions:

1. T(s) = 2000/(s(s+200))

2. T(s) = 100/(s(.1s+1)(.5s+1))

3. T(s) = 1/(s(s+1)(.02s+1))

Q1. Explain why tolerance is not given for a POT resistor.

Q2. List five applications where an LDR can be used.

Q3. Discuss what factors could limit the amount of energy stored in a capacitor and explain why capacitors are not useful to store energy for long time.

Q4. Explain why resistance cannot be measured when the resistor is connected to the circuit.

Q5. If you connect a wire between the terminals of a source, the source is then short-circuited. Explain what outcomes you would expect if a voltage source is short-circuited

1. A 3-phase, 20 kVA, 208 V, 4-pole Y-connected synchronous generator has a synchronous reactance of X_s = 1.5 W per phase. The resistance of the stator winding is negligible. The machine is connected to a 3-phase 208 V infinite bus. Neglect losses.

1. The field current and the mechanical input power are adjusted so that the synchronous machine delivers 10 kW at 0.8 lagging power factor. Determine the excitation voltage E_f and the power angle d.
2. The mechanical input power is kept constant but the field current is adjusted to make the power factor unity. Determine the percent change in the field current with respect to its value in part (a).