Unitized Substations

Switchgear Power Systems’ ability to design, engineer and manufacture metal-clad and metal-enclosed switchgear, transformer disconnects, and custom low voltage switchgear (low voltage switchgear is not yet illustrated on this site) presents yet another area of expertise in the unitized substation market.

Our flexible approach and ability to offer switchgear across the low and medium voltage spectrum gives you a viable source in the unitized substation market.

SPS will work with you to supply the complete system including the transformers or work closely with you to co-ordinate engineering and design when you supply the transformers, or the primary or secondary portions of the substation.

Portable and Flexible

SPS supplied eight 34.5kV to 4.16kV units to a major US utility. The 3750 kVA transformer contained an automatic load tap changer. The switchgear was designed for future 15kV operation and operate initially at 5kV. The portable skid design allowed this customer to build “instant substations” by purchasing the switchgear and the transformers mounted on the skid at the factory. SPS designed the oil containment bin with automatic water drainage incorporating oil traps/filters in the drainage system.

Speed and Design/Build

These 5kV stainless steel unitized substations were concurrently designed with the specifying engineer and then manufactured and shipped within eight weeks to meet the end user’s schedule. The custom paint, medium voltage switch, dry-type transformer, and low voltage breaker integrated with the control system were designed to fit a very compact retrofit space on a ship-loading crane. Hurricane-resistant air louvers/filters, solid bottom, gasketed doors and provisions for customer-supplied drives units were key factors in the design of these unitized substations.

Retrofit Replacement

During an annual inspection / test, our customer determined that the transformers and switchgear at multiple sites of the facility needed to be replaced. We sourced the liquid-filled transformers and designed the switchgear with a selector switch arrangement to match the existing footprint and conduit locations of the original switchgear/transformers.

Flexible Options:

Mild steel, stainless steel or aluminum construction; motor operators; relays and control devices; third party certification; special sizes; NEMA 1, 4, 3r non-walk in, 3r walk in, and PDCB construction; seismic ratings; skid mounted; special colors, etc are just a few of the readily available options from SPS.



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