Distribution transformers for Colombia

Medium voltage by network operator

13.2 kV and 34.5 kV are the most common distribution voltages; 11.4 kV is still used in Bogotá and parts of Santander.

Low-voltage systems in operator specifications

• Enel Colombia, oil-immersed: 208/120 V, 380/220 V, 480/277 V
• EPM group, three-phase oil-immersed: mainly 220/127 V, also 480/277 V and 400/231 V; single-phase 240/120 V

Construction details operators ask for

• Vector group Dyn5 with the neutral brought out and solidly earthed (EPM group and Enel Colombia)
• Tapping: ±2 × 2.5 % (EPM group); +1 / −3 × 2.5 % (Enel Colombia)
• Maximum impedance (Enel Colombia, oil-immersed): 3.0 % for 30–45 kVA, 3.5 % for 75–112.5 kVA, 4.0 % for 150–500 kVA
• Site altitude: Enel Colombia designs for 2,700 m (Bogotá). State the altitude of your site — it affects insulation and cooling.
• Typical three-phase ratings in operator catalogues: 15, 30, 45, 75, 112.5, 150, 225, 300, 400, 500 kVA; dry-type up to 1,000 kVA (Enel Colombia)

RETIE product certificate

Under RETIE (Ministry of Mines and Energy Resolution 40117 of 2024, as amended in 2026), distribution and power transformers of 3 kVA and above and above 100 V need a product conformity certificate issued by a certification body accredited by ONAC.

For imported transformers the certificate must be valid before customs release. Producers and importers must also be registered with the SIC. Include RETIE certification in your enquiry so it is planned into the delivery time.

What our published ratings cover

• Pad-mounted transformers (IEEE/ANSI C57.12, 60 Hz): the published HV list includes 11.4 kV and 13.2 kV at BIL 125 kV; ratings 30–3000 kVA, including 45, 75, 112.5, 150, 225, 300 and 500 kVA; 480Y/277 V is among the published LV options.
• 208Y/120 V and 220Y/127 V low voltage, the Dyn5 vector group and 34.5 kV: quoted on request to the operator’s specification.
• Oil-immersed S11 / S13 loss values on this site are 50 Hz guarantees. 60 Hz units for Colombia are designed and quoted per order.

Send with your enquiry

• Network operator and site (city, altitude)
• Rated power (kVA), HV and LV, vector group, tapping range
• Type: oil-immersed, pad-mounted or dry-type; indoor or outdoor
• Quantity, required delivery date, and the RETIE certification body if you already have one