I am trying to install a low voltage system. I already have an older 200 watt transformer. It has 4 terminals (2 Load, 2 COM), and a High/Lo switch. I can't find any manual or instructions on how to connect this, because all the new transformers only have three terminals. How do I connect my wire to this? Do I need to use all 4 terminals? What is the High/Lo switch for? Am I supposed to run one wire from two of the terminals, and come back and connect the other end of the wire to the other terminals?
Try out one fixture before doing a permanent installation. You'll connect one of the wires to the load and one to the common. The Hi-Lo switch is probably a switch to go from 12 volts to +/- 14 volts- not a big deal. Make sure the transformer has a built in circuit breaker or fuses and that the transformer gets plugged into a GFI outlet. Keep the total wattage about 10% below the transformer rating.