Glossary · Electrical engineering and control panels
Power supply
Also known as: Electrical supply, Supply voltage
German: Spannungsversorgung
In electrical engineering, the power supply of a machine, cabinet or device is the provision of electrical energy at the required voltage, current and quality, including the incoming supply, its protection and the distribution to loads.
- Control panels
In one sentence
The power supply provides electrical energy at the required voltage and quality to a machine, cabinet or device, including distribution.
Example
The machine's power supply is a 400 V three-phase feed with a main disconnect, from which a transformer and 24 V DC power supply units derive the control voltages.
How it applies
- Engineering: Define supply voltage, frequency, network type (TN, TT, IT), short-circuit current and permissible voltage variations. IEC 60204-1 contains requirements for incoming supply, disconnecting devices and protection of machine electrical equipment.
- Installation: The customer's supply must match the machine's requirements; mismatches are a common commissioning issue.
- Documentation: State supply requirements in the installation instructions and on the nameplate. Maintenance manuals must describe the supply disconnecting device and its use for Energy isolation.
Power supply vs. power supply unit
"Power supply" is the function or the incoming energy. A Power supply unit is a device that converts one voltage into another, for example 230 V AC into 24 V DC. In German, "Spannungsversorgung" and "Netzteil" make the same distinction.