Ammeters and voltmeters used in sinusoidal AC power systems indicate which of the following values of the waveforms measured?()
A、A.Peak value
B、B.Root-mean-square value
C、C.Average value
D、D.Maximum value
A、A.Peak value
B、B.Root-mean-square value
C、C.Average value
D、D.Maximum value
A、pyrostats and a voltmeter B、a gas-filled bellows, a tube and a pressure gauge C、thermocouples and a voltmeter D、ammeters and thermocouples
A、both meters in series with the resistance B、both meters in parallel with the resistance C、the ammeter in series and the voltmeter in parallel with the resistance D、the ammeter in parallel and the voltmeter in series with the resistance
A、A.both meters in series with the resistance B、B.both meters in parallel with the resistance C、C.the ammeter in series and the voltmeter in parallel with the resistance D、D.the ammeter in parallel and the voltmeter in series with the resistance
A、A.shunt B、B.high-resistance coil in the armature circuit C、C.low-resistance coil in the armature circuit D、D.shunt and a coil of high resistance