Transformer Mounting

Transformers are installed using one of three methods, chosen based on the transformer’s physical dimensions and weight: suspended from a trapeze attached to the overhead structure, mounted on a wall or column, or positioned on the floor or a platform. Irrespective of the mounting location, vibration isolators are commonly integrated into the design to minimize the transmission of the transformer’s vibrations to the building components.

Trapeze Mounting (Suspended from Structure)

Trapeze mounting of a transformer refers to a method of installation where the transformer is suspended from overhead supports, typically using metal rods or chains resembling a trapeze. This mounting method is often employed when there is limited space on the ground or when the transformer needs to be positioned above obstacles.

In trapeze mounting, the transformer is hung securely from the support structure (provided the support structure is designed to take the weight of the transformer), ensuring that it remains stable and level. This type of installation requires careful consideration of the weight of the transformer, the strength of the support structure, and factors such as wind loads (for outdoor) and vibration.

Trapeze mounting is commonly used in indoor installations where floor space is at a premium. It allows for efficient use of available space and can simplify maintenance and access to the transformer when needed. Additionally, it helps protect the transformer from potential damage caused by flooding or other ground-level hazards.

Transformers above ceiling:

While transformers can be mounted above accessible ceilings, it is highly recommend to limit the size of the transformer to 45kVA or below. Some codes and jurisdiction do not allow transformers 45kVA and greater to be installed above ceilings. Equally as important is accessibility, most codes do not allow transformers above hard ceilings.

Wall Mounting

Wall mounting of a transformer involves fixing the transformer directly onto a wall or a sturdy vertical structure. This method is commonly used when floor space is limited or when it is desirable to keep the transformer elevated for various reasons such as accessibility, safety, or space optimization.

Transformers with a rating of 75 kVA or lower are generally suitable for wall mounting provided the wall or supporting structure is capable of bearing the weight safely. Transformers designed for wall mounting typically come with specific mounting brackets or flanges that allow for secure attachment to the wall. These brackets are usually made of sturdy materials such as steel.

Other Considerations

Ventilation and Access: Adequate ventilation and access space around the transformer must be maintained to dissipate heat generated during operation and to facilitate maintenance and inspection tasks.
Vibration Isolation: Vibration isolators may be used to minimize the transmission of vibrations from the transformer to the wall and surrounding structures, reducing noise and potential structural damage.
Siesmic Considerations: Flexible specially designed electrical connections are used to attached the transformer to the building. These connections allow for movement during an earthquake without causing damage to the transformer or the surrounding infrastructure.

Floor Mounting

Transformers of all sizes and ratings can be mounted directly to the floor or onto a suitably designed platform. When mounting a transformer to the floor, it’s common to include a concrete housekeeping pad as part of the design. While not mandated by code (in most jurisdictions), this pad serves as a stable and level surface for mounting the transformer. Mounting the transformer on a concrete pad simplifies maintenance and cleaning around the area. This prevents debris accumulation and flood/water from entering the transformer.

** Note that information shown is for reference only. Please consult your local codes and by-laws for requirements specific to your area.