the previous owner installed a set of halogen lights in the crawlspace of our house. i am planning on doing some work under the house and i wanted to get them working again. the first light has 3 sets of wires coming into it. one is from the breaker box, one goes to the next light in the series and the third goes to the switch. no volts at the switch when it is off and 50 volts ac when it is on. i have replaced all of the lights and they still do not work.
Where the three cables or sets of wires come in -- connect the white of the breaker box cable (power feed) to the white of the ongoing light cable and white of the light already there (neutrals). Connect the black of the switch cable to the black of the ongoing light cable and the black of the light already there. Connect the other two wires together.
At the other lights you should match up the whites and match up the blacks.
At each box, connect all the grounds (bare or green) together as a separate bundle. If you measure voltage at a switch, measure between a switch terminal and ground, not between the two switch terminals. Assuming everything is wired properly, the power wire will always read 120 volts, the (black) wire to the lights reads 120 volts only when the switch is "on".
The good conscientious technician or serviceperson will carry extra oils and lubricants in case the new pump did not come with oil or the oil was accidentally spilled, so the service call can be completed without an extra visit.