USCG Exam PracticeAC circuits and theory
An AC voltmeter connected to a shipboard 440 V distribution panel reads 440 V. What type of value does this reading represent?
- A. Peak value
- B. Peak-to-peak value
- C. Average value of one half-cycle
- ✓ Root-mean-square (RMS) valueCorrect
Why D is correct
AC voltmeters and ammeters read RMS values, which is the effective value equivalent to the DC value producing the same heating effect. The 440 V nameplate rating is an RMS value; the actual peak voltage is approximately 622 V. (NEETS Mod. 2 §1-2)
Cited:NEETS Mod. 2 §1-2