# Electrical Terms

### Acronyms

kVA | Kilo Volt Amperes |

kW | Kilo Watts |

V | Volts |

I | Ampere or Current |

1Ø | Single Phase (One Phase) |

3Ø | Three Phase |

ATS | Automatic Transfer Switch |

AVR | Automatic Voltage Regulator |

Hz | Hertz (Frequency) |

**Ampere (Amp): **

A unit measure for the flow (current) of electricity. Typical service to a residence is 100 amps; 200 amps is required for homes with electric heat.

**Kilovolt (kV):** 1000 volts.

**Kilo-volt-ampere (kVA):**

A measure of electrical load on a circuit or system: single phase = amperes x voltage / 1000 three phase = amperes x voltage x 1.732 / 1000.

**Kilowatt (kW):** 1000 watts.

A measure of electrical load on a circuit or system – related to kVA: single phase = amperes x voltage x power factor / 1000 three phase = amperes x voltage x power factor x 1.732 / 1000.

Kilowatt Hour (kWH):

The work performed by one kilowatt of electric power in one hour. The unit on which the price of electrical energy is based. A 1000 watt light bulb operating for one hour would use one kWh.

**Single Phase Power:**

(Typically 230V AC in Africa) is carried between two wires, live and neutral and sometimes a third ground wire for safety. The frequency of AC voltage is 50 or 60 Hz. Single-phase power is used in many applications, for example to power all typical home electrical appliances, you get single-phase power from a normal electrical outlet at home.

Three Phase Power:

Is very common and is a more efficient use of conductors. Voltage is carried through three conductors 120° out of phase with the other two. Three-phase power provides a more efficient means of supplying large electrical loads like motors, and is used more in industrial areas.