Glossary
Transformer substation (centro de transformación, CT)
An installation with one or more transformers that steps medium voltage down to the 400/230 V low voltage used by homes, shops and warehouses. It may belong to the distributor or to a customer, the so-called customer-owned CT.
What a centro de transformación is
A centro de transformación or CT is a transformer substation (a transformer station or pad-mount transformer in US usage): the place where electricity passes from medium to low voltage. Inside there are one or more transformers, switching and protection cells and the low voltage board feeding the lines to buildings. It can be a prefabricated kiosk, a ground floor or basement room, or a pole-mounted unit in rural areas.
Utility CT and customer-owned CT
- Utility CT (CT de compañía): owned by the distributor and supplying many customers in an area. The distributor maintains it.
- Customer-owned CT (CT de abonado): owned by one customer, such as a warehouse, hotel, shopping centre or factory, that buys power at medium voltage. The owner must maintain it with a company authorised for high voltage.
When a new area is developed, the developer usually builds the CT and then hands it over to the distributor.
Owner obligations
CTs are governed by the High Voltage Regulations, Royal Decree 337/2014. ITC-RAT-23 sets checks and periodic inspections every 3 years by an inspection body, plus maintenance by an authorised company. A neglected CT can cause outages across the whole installation and serious risks.
When you will need one
- When opening a warehouse or factory with high power demand that low voltage cannot meet.
- When adding machinery, ovens or cold rooms.
- When installing many EV chargers in a car park, where rapid charging often needs a lot of power.
Our part
We design and build the low voltage installation downstream of the CT and coordinate with the high voltage company. See medium voltage coordination in Seville, Spain.
Related services
Medium voltage
Transformer substation maintenance in Seville, Spain, coordinated for you: if your company has its own substation, we coordinate its maintenance and statutory inspections with a company licensed for high voltage, which carries out the medium-voltage work. Pulso Eléctrico takes care of all the low voltage, from the main switchboard to the last machine, so you have a single point of contact.
Industrial warehouses
We carry out the warehouse electrical installation in Seville, Spain and on its industrial estates: supply connection, switchboards, cable trays and conduits, power sockets, lighting, earthing and power for cold rooms, with project and legalisation. When the warehouse needs a transformer substation, we coordinate it.
Industrial maintenance
Industrial electrical maintenance for businesses in Seville, Spain: scheduled inspection plans for switchboards, motors, lines, lighting, UPS units and generators, thermal imaging to get ahead of breakdowns and call-outs for the ones that still happen, in warehouses, shops, offices and residential buildings with industrial-type installations.
Need an electrician in Seville, Spain?
Call us or send a WhatsApp message with a photo of the job. You get a fixed quote before any work starts.