Waveform RMS and Average Values
Full Wave Rectified
Half Wave Rectified
AC Superposed on DC
Periodic Half Sinusoids
Square Wave
Sawtooth Wave
Trapezoidal Wave
The standard formula for calculating the RMS (Root Mean Square) values for a waveform, I(t), is:
The tables below show equations for calculating the typical waveform RMS and average values.
Current Wave Shape |
Configuration |
IRMS |
IAVG |
Sine Wave |
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0 |
Current Wave Shape |
Configuration |
IRMS |
IAVG |
Full Wave Rectified Sine Wave |
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0.637Ipk |
Current Wave Shape |
Configuration |
IRMS |
IAVG |
Half Wave Rectified Sine Wave |
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0.318Ipk |
Current Wave Shape |
Configuration |
IRMS |
IAVG |
Direct Current with Superposed Sine Wave |
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Idc |
Current Wave Shape |
Configuration |
IRMS |
IAVG |
Half-Sinusoids of Duration T and Frequency f |
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(2fIpkT)/ p |
Current Wave Shape |
Configuration |
IRMS |
IAVG |
Square Waves of Duration T and Frequency f |
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fIpkT |
Current Wave Shape |
Configuration |
IRMS |
IAVG |
Sawtooth Waveform of Duration T and Frequency f |
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0.5fIpkT |
Current Wave Shape |
Configuration |
IRMS |
IAVG |
Trapezoidal Waveform of Frequency f |
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fIpk( d+T) |