Question 446Electricity/Electronics - QMED70% to pass
You are troubleshooting the control circuit shown in figure "A" of the illustration utilizing on-line techniques. With the start button depressed, the following readings are obtained with a voltmeter: (Refer to Illustration EL-0123
AI Explanation
The correct answer is B.
This is because when the start button is depressed, the voltmeter should read the voltage at point B, which is the input voltage to the control circuit. The other points (A, C, and D) are internal to the circuit and would not directly indicate the input voltage.
The other options are incorrect because A, C, and D do not represent the input voltage to the circuit, which is the key parameter being measured when troubleshooting the control circuit.
Related Questions
#444 As shown in figure "A" and "B" of the illustration, the potable water pump is short- cycling by the action of the pressure switch as a result of an unusually high level in the potable water hydro-pneumatic header tank. What is most likely the cause? Illustration EL-0043 #445 If a magnetic controller relay fails to drop out when the coil voltage is removed from the relay, what is the probable cause? #447 A loud buzzing noise coming from the contacts in a magnetic controller can be caused by what condition? #448 If a digital multimeter is set up as shown in figure "A" of the illustration to test an AC contactor coil, what would the display read if the coil is open-circuited? Illustration EL-0214 #449 What is a common type of protective covering used on electrical conductors?