Importing distribution transformers into Nigeria: SONCAP, Form M and NEMSA, step by step

Start with the connection specification

Ask the DisCo or EPC to confirm the connection voltage, secondary voltage, vector group and tapping requirements before requesting a firm offer. Use the connection specification as the common reference for the purchase enquiry and conformity discussion. Do not treat a catalogue model name as approval for the intended connection.

The NERC Distribution Code, clause 4.3.1, lists nominal voltages including 33 kV, 11 kV and 415 V. For those voltages, its operational ranges are respectively 31–34.98 kV, 10.45–11.55 kV and 390.1–439.9 V. These are network values, so ask the receiving utility to settle the transformer nameplate and tap selection. [4]

Our published S11 range includes 11 kV primary and a 415 V secondary option, with Dyn11, Yyn0 and Yzn11 vector groups and ±2 × 2.5 % tapping. Frequency is 50 Hz. Published oil-immersed loss tables for 33 kV are on request; the compact substation range includes 11 kV and 33 kV. Ask for the relevant configuration rather than applying an 11 kV loss table to a different voltage class. [6, 7]

Keep the certificate names and owners clear

SONCAP is pre-shipment verification of conformity. SON describes verification and testing in the exporting country, followed by a SONCAP Certificate where goods comply, or a Non-Conformity Report where they do not. Its conformity activities include physical inspection, sampling, accredited laboratory testing, process and system audits, and documentary checks. [1]

The document chain includes a Product Certificate, a Certificate of Conformity and a SONCAP Certificate. SON issues the shipment certificate after receiving the CoC from an Independent Accredited Firm. The Product Certificate is used for Form M; the shipment certificate is used to process the PAAR for customs clearance. Keep the exporter and importer responsibilities explicit in the order paperwork. [1, 2]

SON lists PC1 for unregistered Route A, PC2 for registered Route B and PC3 for licensed Route C. PC1 is valid for six months and a single use; PC2 and PC3 are valid for twelve months and multiple use. Ask the IAF which route applies to the exporter and product rather than assuming a route from the quantity ordered. [1, 2]

Agree conformity evidence before the goods leave

New distribution transformers are not in the exception list on the SON SONCAP service page. Confirm the HS code and applicable conformity requirements with the IAF and clearing agent before opening the import file. SON says IAFs are not allocated territories, so the exporter may choose any appointed IAF. [1]

For Route A, Cotecna describes acceptance of reports from ISO/IEC 17025 accredited laboratories, a Request for Certification and physical inspection before shipment. Send the proposed specification to the IAF and agree what evidence it will accept. A catalogue entry is a useful specification reference, but ask separately which test documents must accompany the certification application. [3]

Request the factory routine-test scope and the documents required for the order, and agree them with the IAF before production. Treat this as a purchase requirement to confirm. This guide does not establish that a particular factory certificate or test report is available for your shipment.

Plan clearance and energising as separate checks

SON states that a FIRS Tax Identification Number registered on the trade portal is needed to process SONCAP. One SONCAP Certificate covers one PAAR consignment and one entity; it cannot be reused for several consignments. The importer should therefore check that the shipment and certificate details match the intended clearance file. [2]

SONCAP cannot be processed after the consignment has left the country of origin. SON warns that regulated goods arriving without the shipment certificate may face detention, testing and possible destruction at the importer’s expense. Check the SON FAQ for current fees; do not budget from an old quotation or a remembered fee schedule. [2]

After import clearance, NEMSA’s installation requirement still applies. Its mandate paper says installations must be tested, inspected and certified fit and safe by the Chief Electrical Inspector of the Federation or a NEMSA electrical inspector before use or interconnection with public supply. Ask the installation contractor to coordinate that stage before energising. [5]

Step-by-step checklist

1. Importer/EPC: obtain the DisCo connection specification and confirm voltage, secondary voltage, vector group, tapping and installation requirements. [4, 6]
2. Importer and exporter: the importer prepares its registered TIN and Form M process with its bank; the exporter applies to an IAF for the appropriate Product Certificate and agrees the required evidence. The PC is needed before Form M. [1, 2, 3]
3. Exporter: arrange production and the agreed factory routine tests; prepare the documents and inspection access requested by the IAF. Confirm the test scope for this order.
4. Exporter/IAF/SON: submit the RFC and complete physical inspection before shipment; the IAF supplies the CoC, then SON issues the SC to the importer. [1, 2, 3]
5. Importer: check the SC before authorising shipment, then use it for the PAAR and customs clearance for that consignment. [2]
6. Importer/installation contractor: arrange NEMSA testing, inspection and certification of the installation before use or public-network interconnection. [5]

Frequently asked questions

Related markets and transformers

• Nigeria market specifications
• s11
• s11 · 630kva 11kv

Sources

Bracketed references correspond to this list. Product figures refer to Jinying’s published specifications; worked-example factors are identified as assumptions.

1. SON — SONCAP service — https://son.gov.ng/soncapservice/ · accessed 2026-10-24
2. SON — SONCAP FAQ — https://son.gov.ng/soncap-faq/ · accessed 2026-10-24
3. Cotecna — Route A certification process — https://www.exports-to-nigeria.com/en/services/certification-process/route-a · accessed 2026-10-24
4. NERC — Distribution Code v01, clause 4.3.1 (AEDC copy) — https://www.abujaelectricity.com/wp-content/uploads/2016/04/Distribution_Code_v01.pdf · accessed 2026-10-24
5. NEMSA — Mandate and Enforcement Powers — https://nemsa.gov.ng/wp-content/uploads/2019/05/Paper-1-NEMSA-Mandate-and-Enforcement-Powers.pdf · accessed 2026-10-24
6. Jinying — published S11 specifications — https://jinyingtransformer.com/oil-immersed/s11/ · accessed 2026-10-24
7. Jinying — compact substations — https://jinyingtransformer.com/compact-substations/ · accessed 2026-10-24