Waukesha® UZD® On-Load Tap Changer (LTC) for Transformers

The Waukesha® UZD® load tap changer is a field-proven design. When the minimally required maintenance is performed, UZD has a reliability rate of 99.95% for units built since 1997.

Designed for high speed, reliable operation and reduced maintenance, the Waukesha® UZD® offers important features with benefits:

BUE Motor Drive Mechanism

Charges the spring battery operating the load tap changer; housed separately in an air-filled compartment. Located at a convenient height and not in the oil-filled switching compartment. Readily accessible at ground level for inspections and maintenance.

Spring Drive Mechanism

Tap changer can be operated manually while energized and carrying load. Stored energy in the spring mechanism results in high speed operation and minimum arcing time. Each tap change is consistent and unaffected by voltage interruptions or manual hand cranking speed.

Load Tap Changer and Series Transformer System

For applications with greater than 600 ampere current ratings, a series transformer is recommended to allow for an optimal volts/turn design of the main transformer windings, even step regulation and smaller leads while facilitating a reduction in current through the LTC contacts for less contact wear and longer life; a power-class series transformer design is recommended for high reliability.

Single Arm Design

Single arm simultaneously operates both the tap selector and arcing contacts for a simple basic design with few parts that helps reduce operating and maintenance costs.

Other Features

  • Designed to withstand full vacuum in tank without bypass piping to equalize pressure.
  • Large opening to tap changer compartment helps make inspections quick and easy.
  • Waukesha's design utilizes just three openings into the main transformer tank protected with O-ring gaskets for maximum protection from leaks—fewer openings means less maintenance.
  • Compact design requires only 100 gallons of oil to drain and replace.
  • Full-featured control compartment equipped to meet customer requirements.
  • Meets all requirements of IEEE standard for Load Tap Changers (IEEE C57.131-1995)

Whatever the market or customer need, when it comes to transformers, components or service support, SPX Waukesha quality will be there for you!

For more information please contact our Waukesha® Components group at 800-338-5526, contact the SPX Waukesha Sales & Service Representative nearest you or utilize our on-line resource: General Inquiry Form.




Economics Benefits of Low Current LTC 68KB
Strategy of Low Current LTC and Series Transformer 363KB
LTC Ordering Sheet 673KB
Waukesha® UZD® Brochure 1MB

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