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What is indicated by the deflecting torque interaction between Coils A and B?
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It indicates the resistance value across the machine's terminal and body.
What are the two types of high voltage Megas based on their operation?
Motor operated and power operated.
How does the clutch mechanism in a Mega maintain constant voltage?
It slips at a predetermined speed to ensure constant voltage during testing.
What are the roles of Coil A and Coil B in the Mega insulation resistance measurement?
Coil A functions as a voltage coil, while Coil B functions as a deflecting coil.
Explain the initial state of the Mega when terminals X and Y are free.
No current flows through Coil B, causing Torque from Coil A to indicate infinity, suggesting no resistance.
Which component of the Mega is connected to the body of the equipment for grounding?
Terminal Y.
How does the interaction of torques in the Mega help in measuring insulation resistance?
Torque from Coil B interacts with Coil A's torque to provide a resistance value reading.
Why could different available voltage levels be necessary in a Mega?
Different voltage levels allow the Mega to test insulation resistance across various types of equipment and applications.
Describe the operational process when the crank handle of a Mega is rotated.
Rotating the crank handle generates voltage in the generator, which is applied to Coil A through resistance R1.
List the typical voltage levels generated by a Mega.
500 volts, 1000 volts, 2500 volts, and 5000 volts.
Why is it essential for the Mega's clutch mechanism to slip at a predetermined speed?
To maintain constant voltage during testing, which is crucial for accurate resistance measurements.
What happens during the measurement when terminals X and Y are connected?
Current flows through Coil B, and the deflecting torque interacts with Coil A's torque to indicate the resistance value.
What function does the generator in a Mega perform?
It generates voltage by rotating the armature when the hand-driven cranked lever is turned.
What is the purpose of the Testing Terminal X in a Mega?
It connects to the hot terminal of the equipment being tested.
Differentiate between the roles of the hot terminal and the body of equipment in Mega testing.
The hot terminal is connected to Terminal X for applied voltage, and the body is grounded via Terminal Y.
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