The disorder results from overproduction of collagen, a naturally occurring protein found in the skin. It is unknown what causes this overproduction of collagen to occur but the immune system is believed to play a significant role. Morphea is not contagious or passed down in families.
A typical US household voltage is 120/240 V, 60 hz, single phase. There is a tolerance and the actual measured voltage is rarely exactly 120 volts. A common reading at my house is 117 volts. Industrial motors are made and rated in multiples of 115V (115, 230, 460, and 550Vac) for use on line voltages in multiples of 120 V (120, 240, 480, and 600 Vac).
120 and 240 Volts. The power delivered to your home is 120 or 240 volts. That means it's the standard voltage as measured at the transformer outside your home. Nominal voltage can vary up to plus or minus 5 percent from its stated definition.