See also: Food (homonymy)

The term of power supply indicates a whole of systems able to provide electricity to the apparatuses functioning with this energy. More specifically, the power supply is the equipment which draws the Electric current from a Electrical communication and provides it, in an adapted form, with another apparatus: running, tension and Frequency as required by the apparatus and in a stable and constant way.

Integrated food

In the majority of the apparatuses electric household appliances S and office, some circuits require a power supply of characteristics different from that distributed starting from the individual electric meters.

At the entry of the apparatuses, before or integrated into the food, one finds a parasitic filter intended to remove the entering, but especially those generated by the food itself and those of the apparatus which could disturb the network.

One can distinguish two principal types from food:

• Those of low power which are only used to feed a small portion of the apparatus: the majority of the apparatuses electric household appliances S a minimum sophisticated, can break up into two distinct electric parts, the control circuit and the power circuit .
• the control circuit , since it is used as interface with the man is in Très low tension, a food transforms 230 V into a tension (lower than 50 V, generally 12 V) compatible with the control circuit.
• the power circuit is seen supplied with the tension of the sector through a Organe of Commutation controlled by the control circuit.
• And those by which forward all the electricity consumed by the apparatus, those often provide several separated power, assigned to different tasks.

Separate food

Technological advances supporting an increasingly reduced consumption of the apparatuses, small apparatuses domestic and offices: Receiving radio operator, Telephone, Lamp of office, Printing, are fed for safety reasons and, sometimes of esthetics, in Très low tension using an external power supply unit. Frequently this block is only one simple transformer step-down transformer, sometimes associated with a Redresseur delivering a tension continues, sometimes a Regulator voltage supplements this food.

Food of laboratory

In the Workshop S and Laboratory S where one conceives, tests or, the switchgear and electronic repairs, of the food more sophisticated much make it possible to feed with a maximum of safety, the parts of the apparatuses under examination or test. All the parameters of the currents and tensions to be delivered can be regulated separately and very precisely to avoid any damage with the materials and the personnel.

Protective system

• Lightning conductor

• Put at the ground
• Fusible Shielding
• Circuit breaker

Standard names

• VHV: Very high voltage (this name currently any more does not exist in the French legislation)

• HT: High voltage
• BT: low tension
• TBT: Very low tension

See too

• Normal Food Help

• railway System of electrification

• linear Food

• Food with cutting