Welcome to AC voltage conversions.
The following are the types of values used to represent ac voltages. Peak,
RMS, and average. Note that the average value of a sine wave over one full cycle
is actually zero. The 0.636 value pertains to a half cycle and peak-to-peak. It is very
important for technicians to be able to convert one type of voltage to another.
There are several ways to convert voltages. When doing conversions,
numbers need to be memorized and calculations using multiplication and division are required
to simplify conversions from one value to another. This learning object will require multiplication
only, memorization of four numbers, and utilization of the peak voltage as a reference.
The following table is used as a reference for converting from one ac value to another. AC value,
the value given, is listed in the left column. The value to be solved for
is listed across the top. The given voltage value must be multiplied by a conversion
number in the table to obtain the other type of voltage. The conversion number to be used
is located in the box that intersects the given voltage and the new value to be solved for.
To convert RMS voltage to peak voltage, follow the example. Given an initial ac voltage value
of 120 volts rms, use the formula from the table to calculate peak voltage as shown.
To convert average voltage to peak voltage, follow the example. Given an initial ac voltage value
of 107.6 volts average, use the formula from the table to calculate peak voltage as shown.
To convert peak voltage to rms voltage follow the example. Given an initial ac voltage value
of 169 volts peak use the formula from the table to calculate rms voltage as shown.
To convert peak voltage to average voltage follow the example. Given an initial ac voltage value
of 169 volts peak, use the formula from the table to calculate average voltage as shown.
To convert between rms and average voltage use peak voltage as a reference. First convert the
given value to peak voltage, then convert from the peak voltage to the desired value.
For example when converting 120 volts rms to average first convert to peak as shown.
Then convert peak to average as shown.
To convert from an rms or average voltage to peak to peak
first convert the given voltage to peak, then multiply the peak voltage by 2.
For example convert 107.6 volts average to peak to peak. First convert to peak as shown.
Then multiply peak voltage by 2.
To convert from peak to peak voltage to rms or average voltage, multiply the peak-to-peak voltage
by 0.5 to obtain the peak voltage. Then convert the peak voltage to the desired rms value. For
example convert 338 volts peak to peak to an rms value. First convert to peak voltage as shown.
Then convert the peak voltage to rms.
See if you can remember the four conversion factors.
You have completed this activity AC voltage conversions.