Glossary · Automation fundamentals, platforms and components
Transformer (electrical)
Also known as: Power transformer, Control transformer
German: Transformator
In electrical engineering, a transformer is a static device that transfers electrical energy between two or more circuits by electromagnetic induction, usually changing the voltage level. In machines, control transformers and isolating transformers supply control circuits at lower voltage and with galvanic separation.
- Automation components
In one sentence
An electrical transformer transfers energy between circuits by induction, usually changing voltage, for example to supply machine control circuits.
Example
The machine's control circuit is fed from a 400 V / 230 V control transformer so that one side of the control voltage can be earthed.
How it applies
- Engineering: IEC 60204-1 calls for control circuits supplied from the mains to be fed through a transformer with separate windings, with exceptions stated in the standard. Transformers are sized for continuous load and inrush currents of connected devices.
- Maintenance: Transformers get hot and can produce high inrush currents when switched on. Protective devices must be selected accordingly.
- Documentation: Circuit diagrams show primary and secondary voltages, rating and protection. In multilingual documentation, add the qualifier "electrical" where the AI architecture Transformer could also be meant.
Electrical transformer vs. AI transformer
The electrical transformer converts voltage levels by induction. The AI transformer is a neural network architecture behind large language models. The two share only the name.