43. What type of contact is an emergency stop button? (a) Momentary, NC (b) Latching, NC (c) Momentary, NO (d) Latching, NO 44. Complete this statement: A starter is required when a motor is to be brought to a stop by means of plugging. 45. Which of the following braking systems can hold a motor stationary once it has stopped? (a) Dynamic braking (b) plugging (c) Friction brake (d) both a and b 46. For an electromechanical relay, the amount of voltage and current required to energize the relay coil is (a) more than what: required to de-energize the coil (b) less than what is required to de-energize the coil (c) the same as the voltage and current ratings of the contacts (d) the same when connected to an AC or a DC source 47. It is possible for a relay coil to be rated for 24 VDC and its contacts to be rated for 240 VAC (a) True (b) False

43. What type of contact is an emergency stop button? (a) Momentary, NC (b) Latching, NC (c) Momentary, NO (d) Latching, NO 44. Complete this statement: A starter is required when a motor is to be brought to a stop by means of plugging. 45. Which of the following braking systems can hold a motor stationary once it has stopped? (a) Dynamic braking (b) plugging (c) Friction brake (d) both a and b 46. For an electromechanical relay, the amount of voltage and current required to energize the relay coil is (a) more than what: required to de-energize the coil (b) less than what is required to de-energize the coil (c) the same as the voltage and current ratings of the contacts (d) the same when connected to an AC or a DC source 47. It is possible for a relay coil to be rated for 24 VDC and its contacts to be rated for 240 VAC (a) True (b) False

Electric Motor Control

10th Edition

ISBN:9781133702818

Author:Herman

Publisher:Herman

Chapter1: General Principles Of Electric Motor Control

Section: Chapter Questions

Problem 9SQ

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