Electrical Engineering

A current shunt is a device with a very low resistance, usually around one ohm. The exact resistance of the shunt is printed on the device for reference, and it is often slightly higher or lower than nominal, for example a 1 ohm shunt may actually have a resistance of .99986 ohms or 1.0002 ohms. A current shunt is not used to control current, however, so I do not know if this is the device you are asking about. It is used to measure current by using a precision voltmeter to measure the voltage drop across the shunt, and then using ohms law to calculate the current. Voltage (Volts) divided by Resistance (Ohms) equals Current (Amps). When the shunt is placed so that it interrupts a circuit, (placed in series), the current flowing in the circuit can be accurately measured with the shunt, without changing the values in the circuit enough to affect it. Many shunts of this type have a large heavy duty resistor that does not overheat easily. The shunt should also have a max current rating listed on it.

A vacuum is a non conductor.

1HP = 746 watts

15 HP = 11190 watts = 11.19 kW

You would need a generator of at least 13kW.

UPS Distributor for 15 Years.

Primary winding carry more current.

We measure the current in one single wire, so no of turns are 1, in secondary the no of turns are higher. so, obviously it has higher voltage then this wire. so, finally as per the transformer rule the secondary carry lesser current than primary.

Similar to DC permanent magnet motor (which I'm assuming you understand); except the stator is not a permanent magnet but an electromagnet. There are 2 separate coils on the stator, which are connected in series with the brushes and armature:

supply ----- stator segment --- brush - armature - brush --- stator segment ----- return

Since the stator coil segments are wired in series with the armature, reversing the supply will *not* change the direction of rotation; as both magnetic fields will reverse together. (But a reversing switch affecting only the armature *will* reverse the rotation.) And since the motor will always turn in the same direction independent of the supply polarity, this means it will work equally well from DC or AC; and the supply frequency will not affect the rotation speed.

When it supplies a resistive load.

closed loop system

A megger would not be suitable for testing insulation resistance of a 13.2-kV transformer, as the transformer's voltage rating is significantly higher than the output voltage from a megger.

It depends on the frequency. At 60 Hertz, with an ordinary two pole synchronous motor, you cannot have an RPM that is greater than 1800, so a six thousand RPM motor has to have a different power supply.

Overhead lines have 'sag' (not 'slack') because the conductors need to be able to expand and contract as the temperature changes. If sag isn't built into the design of the line then, when the conductors contract, they will put undue lateral strain on the supporting poles or towers. It is important that, with maximum sag, the minimum clearance distance between the line conductors and the ground below is always maintained. This safety clearance increases, of course, with line voltage. Allowing for the necessary sag part of the design-process for any overhead line, and achieving it becomes the responsibility of the linesmen when the line is eventually constructed.

Restructuring the existing power system network to achieve better utilization of electrical energy with reduction of losses

B. The field coil (source page 36 of study unit 3, Appliance repair)

A short circuit between adjacent turns of the same winding will cause the turns ratio of the transformer to change. A short circuit of this nature may not cause the transformer to become disconnected, so the situation could last for a long time.

In larger utility transformers, the gases formed by the arcing between turns will collect in the Buchholz relay, situated between the transformer and its expansion tank, which will then initiate an alarm inside the substation.

Power factor can be unity. If the load is purely resistive, then the load current and supply voltage are in phase, and the load will have unity power factor.

You cannot. By definition, the potential of each line must be displaced from each other by 120 electrical degrees, and this is only achievable from a three-phase source.

By referring to the manufacturer's characteristic curves for the fuse. There are different curves for different types of fuse (e.g. rewirable, cartridge, etc.). Essentially, these curve will tell you how quickly the fuse will operate for any value of overload current.

Certainly not in the case of high-voltage circuit breakers. Probably not in low-voltage circuit breakers, as copper is a better conductor and has a higher melting point.

i understand that YNaOd1 represent an auto transformer with HV winding as wye connected and loaded tertiary. Please correct me if i am wrong.

You are probably describing a transformer. The 'high voltage side' of a transformer is the winding with the greatest number of terms. It could be the primary or the secondary winding.

moct is device measure the current by means of faraday's effect..