Question 137Electricity/Electronics - QMED70% to pass
What can be the cause of excessive heat or burning contacts in an operating motor controller?
AI Explanation
The correct answer is B) loose connections or low contact pressure.
Explanation:
Loose connections or low contact pressure in an operating motor controller can lead to excessive heat or burning contacts. This is because poor electrical connections increase resistance, which in turn generates heat. Loose contacts and low pressure can also cause arcing between the contacts, further contributing to excessive heat and potential damage.
The other options are incorrect because:
A) A burned-out operating coil would not directly cause excessive heat or burning contacts in the motor controller.
C) Low motor starting torque is unrelated to the cause of excessive heat or burning contacts.
D) High ambient temperature may exacerbate the issue, but it is not the primary cause of the problem.
Related Questions
#135 The motor fails to start on an attempted startup. With the start button depressed, a voltmeter reading between 1 and 5, as illustrated in figure "A", indicates line voltage available to the control circuit, what should be your next step in the troubleshooting process? Illustration EL-0007 #136 The illustrated motor fails to start and gives a loud hum when the start button is depressed, what should then be your first action? Illustration EL-0007 #138 A capacitor is to be tested with a digital multimeter set up to measure ohms. If the meter is connected to a shorted capacitor, how would the meter display respond? #139 If a digital multimeter is set up as shown in figure "A" of the illustration to test a capacitor, what would the display read if the capacitor is shorted? Illustration EL-0213 #140 What should be done with a capacitor that is obviously discolored due to excessive heat?