Oil-Immersed Transformers for Industrial Factories | Nelink

A factory transformer serves a changing combination of production machinery, motors, ventilation, lighting, and controls. Selecting an oil-immersed unit starts with understanding that operating pattern, not simply adding the equipment nameplates. The purchasing objective is a transformer that fits both the electrical network and the way the factory actually runs.

Define the Duty Before the Rating

Separate connected load from expected simultaneous demand. Record normal production, shift changes, major motor starts, seasonal peaks, and planned expansion. Identify loads that cannot tolerate a production interruption and ask the electrical designer to compare the proposed supply arrangements.

Specify primary and secondary voltages, frequency, phase arrangement, vector group, and neutral requirements. Ask the designer to establish impedance and fault-duty requirements alongside voltage regulation and protection coordination. For mineral-oil-immersed transformers, IEC 60076-7 addresses the relationship between loading, ambient conditions, and thermal ageing; a nameplate rating does not replace that application review.

Coordinate Cooling and the Installation

Provide the actual ambient temperature range, altitude, indoor or outdoor location, and exposure to dust, salt, or chemicals. Confirm the proposed cooling method and any restrictions imposed by the surrounding enclosure or transformer room. Keep building ventilation and equipment clearances within the engineering scope.

Liquid-filled equipment also needs a site-specific fire and spill-control review. Assign responsibility for containment, drainage, access restrictions, and the foundation. Use the selected unit's approved drawings and applicable site requirements instead of carrying a clearance figure from an unrelated installation into civil construction.

Make Offers Comparable

• Request no-load and load losses separately, with reference conditions, tolerances, and the intended verification method.

• List required bushings, cable boxes, gauges, pressure devices, and alarm or trip contacts; distinguish included items from options.

• Confirm the tap arrangement and its operating limitations in the documentation, without assuming automatic voltage regulation.

• Obtain equipment dimensions, operating and shipping weights, foundation loads, and the proposed delivery condition.

Agree the Handover Evidence

Specify drawings, nameplate information, routine test reports, accessory documentation, and installation and maintenance instructions before placing the order. Match the acceptance records to the purchased configuration and record any deviations for engineering approval.

Factory tests and site commissioning have different purposes. Identify who will coordinate the transformer with upstream protection and downstream distribution, and reserve site electrical work for qualified personnel under an approved plan. For a Nelink enquiry, include the single-line diagram, load profile, environmental data, and document schedule so that quotations address the same defined duty.