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I picked off 120v from an outlet (parallel) to power a dual switch that inturn will switch on a light and the other to switch on a bathrom fan using a 3/12 with grnd. The circuit is connected through the dual switch by providing the black "hot" wire to the "com" terminal of the dual switch. The other side of one switch will go to the light (wht) and the other side of the second switch will go to the fan (red) and all the grounds and nuetrals are continuously connected respectively. The open wires are waiting to be connected to their respective fixture. With my multimeter on the open wires I turn the switch on and I get 120volts but when I turn the switch off I get a 15volt reading. Is this normal because I am reading through a switch that doesn't have a load on it?