Delta Delta Transformers in San Diego

Delta Delta Transformers in San Diego from ESU. We buy and sell new & used Circuit Breakers, Electrical Power Transformers, Fuses, Switches, Plugs and more for San Diego

A Delta–Delta transformer is a type of three-phase transformer connection where both the primary winding and the secondary winding are connected in a delta (Δ) configuration.

Here’s what that means in practice:

  • Delta connection (Δ): The three windings are connected end-to-end to form a closed loop shaped like a triangle (delta). Each corner of the triangle connects to one of the three phases.

  • Primary side (input): The high-voltage windings are connected in delta.

  • Secondary side (output): The low-voltage windings are also connected in delta.

Key Characteristics

  • Provides a 3-wire system on both primary and secondary.

  • Does not require a neutral conductor.

  • Can handle large loads and is common in industrial applications.

  • Has good fault tolerance: if one transformer in a bank fails, the remaining two can continue supplying power in what’s called an “open delta” at reduced capacity (about 57.7% of the original kVA).

  • Typically used when loads are balanced three-phase motors or equipment, not where single-phase loads need a neutral.

Common Uses

  • Power distribution in industrial plants.

  • Motor loads where a neutral connection isn’t needed.

  • Situations requiring high reliability, since it can still run in open-delta mode.

 

Electrical Supplies Unlimited (ESU) buys and sells new and used electrical equipment in San Diego and surrounding areas, including La Jolla, Sorrento Valley, Miramar, Carmel Valley, University City, and beyond. We specialize in providing both homeowners and businesses with quality products, with shipping available to customers outside our region as well. In addition to circuit breakers and other electrical supplies, ESU also purchases your used transformers.

At ESU, we carry a wide variety of electrical equipment from leading brands such as Westinghouse, Acme, Cutler Hammer, Siemens, Federal Pacific (FPE), Square D, General Electric, and Zinsco. As a fully stocked electrical distributor and wholesaler, our San Diego warehouse offers many different product lines to meet customer needs. Among our featured products are Delta–Delta transformers, available in new, used, and certified options.

When you need a reliable source for transformers, Electrical Supplies Unlimited is your trusted partner in San Diego. We stock Delta–Delta transformers in a range of sizes and capacities to support industrial, commercial, and specialized applications. Whether you need a certified replacement transformer, a used unit for cost savings, or a new installation, ESU has the inventory and expertise to help. Our team is committed to providing quality equipment, outstanding service, and dependable solutions for every customer.