The normal value with which we refer to the voltage is called the rms voltage. It is the root mean square of the instantaneous voltage supply
V _{rms} = Sq. root (v_{1}+v_{2}+v_{3}+v_{4}.....v_{n})/n
Where v_{1}, v_{2} , v_{3} and v_{n} are the instantaneous voltages.
The relation between the rms voltage and the peak voltage is as follows.
V_{rms} = 0.707 x V _{peak}
