| A | B |
|---|
| Induction | To generate a current in a conductor by placing it in a magnetic field and moving the conductor or magnetic field. |
| Insulator | A device that inhibits the flow of current. Opposite of conductor. |
| Ladder diagram | A simplified schematic diagram in which the load lines are arranged like the rungs of a ladder between vertical lines representing the voltage source. |
| Load | A device that converts electrical energy into another form of energy (heat, mechanical motion, light, etc.). Motors are the most common loads in HVAC systems. |
| Multimeter | A test instrument capable of reading voltage, current, and resistance. |
| Ohm | The unit of measurement for electrical resistance. |
| Power | The amount of energy (measured in watts) consumed by an electrical load. Power = voltage × current. |
| Rectifier | A device that converts AC voltage to DC voltage. |
| Relay | A magnetically operated device consisting of a coil and one or more sets of contacts. Used in low-current circuits. |
| Resistance | The opposition to the flow of electrons (i.e., load) |
| Short circuit | A situation in which a conductor bypasses the load, causing a very high current flow. |
| Solenoid | An electromagnetic coil used to control a mechanical device such as a valve or relay contacts. |
| Transformer | Two or more coils of wire wrapped around a common core. Used to raise and lower voltages. |
| Volt | The unit of measurement for voltage. |
| Voltage | A measure (in volts) of the electrical potential for current flow; also known as electromotive force (EMF). |
| Watts | The unit of measure for power consumed by a load. |
