The black wire is going to be the 'hot wire' which means it is carrying a high voltage. According to our research, when you have the three wire setup you have the black, white and bare copper or green wire. The green wire is the ground, which means it has no current carrying through it. This leaves you with the common as the white wire and the black.
The white wire is returning electricity from the load say from a light bulb. Therefore, given the research you should have 110 volts coming from the black wire into the circuit. Older homes use a two-wire connection rather than three and are 110 volts in a circuit. Newer homes using the three-wire connection actually have 220, which splits 110 volts to the black and 110 to the second wire, which can be the red wire. It all depends on what the home has used. In other words, you may find that your home with a 220-volt connection actually has two hot wires with a black and red giving each 110 volts and leaving the white as the return.
It is a bit confusing, but in either answer you should have 110 volts in the black wire because this is the hot wire bringing in the electrical energy and the other wires through the transformer are meant to distribute it. Nowadays it is common to see 220-volt circuit on dryers and other large appliances in order to handle the electricity that comes in given the rating on the wire.
It is best to seek a professional electrician in order to ensure your home is set up properly rather than to do it yourself given the trouble electricity can cause.
The white wire is returning electricity from the load say from a light bulb. Therefore, given the research you should have 110 volts coming from the black wire into the circuit. Older homes use a two-wire connection rather than three and are 110 volts in a circuit. Newer homes using the three-wire connection actually have 220, which splits 110 volts to the black and 110 to the second wire, which can be the red wire. It all depends on what the home has used. In other words, you may find that your home with a 220-volt connection actually has two hot wires with a black and red giving each 110 volts and leaving the white as the return.
It is a bit confusing, but in either answer you should have 110 volts in the black wire because this is the hot wire bringing in the electrical energy and the other wires through the transformer are meant to distribute it. Nowadays it is common to see 220-volt circuit on dryers and other large appliances in order to handle the electricity that comes in given the rating on the wire.
It is best to seek a professional electrician in order to ensure your home is set up properly rather than to do it yourself given the trouble electricity can cause.