Question 46Electricity/Electronics - QMED70% to pass
Before electrical work can be safely undertaken, the equipment must be de-energized, locked and tagged out, and verification must be made that the circuit is actually dead. What testing device is most certain to reliably verify that a circuit is actually dead?
AI Explanation
The correct answer is B) an autoranging digital multimeter.
An autoranging digital multimeter is the most reliable device to verify that a circuit is actually dead because it can accurately measure the voltage in the circuit and confirm there is no voltage present. This ensures the circuit has been properly de-energized before any work is performed, in accordance with electrical safety regulations.
The other options are less reliable - a non-contact voltage tester may not detect low voltages, a solenoid type voltage tester can be affected by electromagnetic fields, and a non-autoranging digital multimeter requires the user to manually select the correct voltage range, which increases the risk of an incorrect reading.
Related Questions
#44 At a minimum threshold, how many milliamps of current through the body produces a condition where most people would experience respiratory paralysis and be unable to breathe while still in contact with the energized conductor? #45 After prior isolation and lock-out/tag-out procedures are performed, which electrical device requires discharging any stored electrical energy before any work may safely begin? #47 At a minimum threshold, how many milliamps of current through the body produces a condition where most people would suffer ventricular fibrillation and could only be resuscitated with a ventricular defibrillator? #48 Which of the following voltage testers would be associated with high quality, be safe to use, and minimize the electric shock hazard? #49 With all other factors considered equal (such as voltage, conducting path through the body and the duration of contact), contact with an energized electrical system conductor of which system type would produce the most damaging effect?