Trans-Rupter II® Transformer Protectors

Trans-Rupter II is designed exclusively for primary-side application on distribution substation transformers. This revolutionary device combines the three-phase tripping, high interrupting ratings, and sophisticated protection capabilities of higher cost circuit-switchers and circuit breakers . . . with the simple installation procedures and minimal maintenance requirements of lower-cost power fuses.

Choose the Version That Fits Your Needs
Model EX is tripped by an external signal provided by a user-furnished differential, sudden-pressure, or overcurrent relay. Model EX is perfect for new installations, and for retrofitting outdated circuit-switcher, circuit breaker, and high-speed grounding switch installations where protective relays and control power are already in place. It’s available with optional motor operators that provide remote-resetting capability.

Model SE features a self-powered overcurrent protection system activated by current transformers on theprimary bushings of the transformer. Digital overcurrent relays provide complete time-overcurrent and instantaneous-overcurrent protection; they’re field-settable and include user-selectable time-current characteristics.

With Model SE there’s no need for external relays, substation batteries, or a control house . . . you can save tens of thousands of dollars over the installed cost of a circuit-switcher or circuit breaker. Model SE is ideal for new installations, as well as for retrofitting overdutied power fuse installations.

No-Maintenance Interrupters,
No-Maintenance Operating Mechanism
Trans-Rupter II interrupters are factory-filled and hermetically sealed, eliminating the hassle and expense of field-filling with SF6. These electrically tripped, resettable interrupters provide 31.5-kA, 3-cycle fault-interrupting performance. There’s no mechanical linkage to adjust or maintain. Trans-Rupter II’s operating mechanisms are likewise sealed for life, protected from the environment.

Shatterproof Composite-Polymer Silicone Insulation
Trans-Rupter II’s interrupter and insulating support column insulation stands up to the most severe environment. The unique patented skirt arrangement on 115-kV and 138-kV pole-units provides enhanced dielectric performance.

Space-Saving, Lightweight Design with Superior Mounting Flexibility
Trans-Rupter II installs on nearly any structure—even on the transformer or source-side disconnect switch. It’s ideal for retrofit of older equipment and for mobile-transformer applications.

A user-furnished, three-pole, group-operated disconnect switch is required to provide visible air-gap isolation during maintenance, and to pick up transformer magnetizing inrush current. Alternately, Trans-Rupter II can be furnished with a space-saving integral vertical-break style disconnect.

S&C Mounting Pedestals are available too, in a variety of heights and phase spacings.