VA rating (volt-ampere) is the apparent power or RMS power rating in an AC circuit. VA is basically equal to the wattage rating in a DC circuit. You can use ohms laws to calculate various RMS values. Looking at 241-6-120-ND as an example, you will see that multiplying the output voltage times the output current gives the VA power rating, dividing power by the output voltage will give the output current, or dividing power by the output current will give you the output voltage.
