DBU

The DBU provides superior performance especially intended for distribution system protection up to an operational voltage of 34.5kV. Because the DBU is available in various current ratings and time-current characteristics, close fusing can be achieved to maximize protection and overall coordination.

DBU Expulsion Fuses utilize the proven performance of boric acid to create the de-ionizing action needed to interrupt the current. Fault interruption is achieved by the action of an arcing rod and a charged spring, elongating the arc through a boric acid chamber upon release by the fuse element. At high temperatures, boric acid decomposes producing a blast of water vapor and inert boric anhydride. Electrical interruption is caused by the steam extinguishing the arc, as the arc is being elongated through the cylinder.

Features

• Suitable for both indoor and outdoor applications.
• Provides a low initial cost alternative to refillable fuses.
• Gives a low arc and mild exhaust fault interruption.
• Available in 3 maximum voltage classes: 17kV, 27kV, and 38kV.
• Speed variations: Standard "E", Slow "E", and "K".
• Amperage sizes from 3 Amps through 200 Amps.

Applications

• Power Transformers
• Feeder Circuits
• Distribution Transformers
• Potential Transformers
• Station Service Transformers
• Metal-enclosed Switchgear
• Pad Mount Switches

Definitions:

• "E" Rated is the standard speed version.
• "K" Rated is the fast acting version.
• "SE" is the time delayed "E" rated version.

Brands:

• Bussmann
• Eaton Cutler-Hammer Westinghouse
• Cooper Power Systems

Data Sheets:

• Data Sheet 1: DBU Fuses