Technical guides · Gailhan workshop
Transformer guides and technical advice
Choosing, sizing, connecting and protecting a transformer: answers from our design office, drawn from what we wind every day in our workshop in Gailhan, France.
- 3articles
- 3categories
- September 2026latest article
Featured
Isolation transformer for boilers: the complete guide
An isolation transformer for boilers gives the boiler a clean neutral and, with its tappings, brings a high supply back to about 230 V. How it works, which VA rating to choose, how to wire…
Bureau d’études
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Earthing System (TNC, TNS, IT): The Key Role of the Isolation Transformer
An isolation transformer can change your earthing system thanks to its winding connection: It can create the neutral. Discover our guide,
How to power a caravan with 12V?
A 12V power supply for a caravan or motorhome must be provided by a 12VDC DC power supply. In this article you'll find more details on how to power your vehicle from the mains.
By range
Guides by transformer family
Each guide leads to the transformers it covers: models, voltages and prices.
Isolation
Galvanic separation of an installation: personal safety, earthing systems, interference.
- Isolation transformer for boilers: the complete guide
- Earthing System (TNC, TNS, IT): The Key Role of the Isolation Transformer
- See the 3 models
AC/DC power supplies
12 or 24 V direct current for LED lighting, caravans or automation.
- See the 14 models
Single-phase
From 230 V or 400 V to 12, 24, 48, 110 or 230 V, for control circuits, lighting and machines.
- See the 12 models
Three-phase
Adapting a three-phase voltage, creating a neutral, supplying a machine or a building.
- See the 5 models
Toroidal
Compact and quiet, for audio, lighting and sensitive equipment.
- See the 3 models
Autotransformers
Changing voltage without isolation: 230 / 110 V, 400 / 230 V, reversible models.
Design office
A question about your installation?
Tell us about your supply and your equipment: we’ll recommend the right transformer, standard or custom-made, and reply within 48 hours.
+33 4 66 80 14 33Monday to Friday, 8 am – 6 pm (French time)