WEG UBW Molded-Case Circuit Breakers

WEG’s UBW series are molded-case circuit breakers designed for reliable branch-circuit protection in commercial and light-industrial panels. They use a thermal-magnetic trip element to protect conductors and equipment against both overloads and short-circuits, with a straightforward catalog scheme that makes selection fast.

Where they fit

• Applications: panelboards, switchboards, OEM control panels, MCC buckets, machine sub-feeds.
• Loads: motors, HVAC equipment, lighting, receptacle circuits, and general distribution.
• Environments: commercial buildings, facilities maintenance, light manufacturing.

Frame & performance options

225 A frame (UBW225) offered in three interrupting classes so you can match available fault current without overspec’ing:

• UBW225N — up to 35 kA @ 480 VAC (≈ 18 kA @ 600 VAC)
• UBW225H — up to 65 kA @ 480 VAC (≈ 25 kA @ 600 VAC)
• UBW225L — up to 100 kA @ 480 VAC (≈ 35 kA @ 600 VAC)

Ampere ratings: common thermal settings from 15 A to 225 A (fixed thermal / fixed magnetic).

Tip: choose N / H / L by matching or exceeding the site’s available fault current (AIC) at the installation voltage; use your coordination study or utility data as the reference.

Construction & features

• Thermal-magnetic trip: fixed thermal (overload) + fixed magnetic (instantaneous fault) protection.
• 3-pole configurations for three-phase distribution.
• Compact footprint with a consistent layout across N/H/L classes for easy standardization.
• Line & load lugs available on the 225 A frame (per datasheet), simplifying install.

Catalog & ordering

UBW part numbers are straightforward and encode the frame, interrupting class, ampere setting, and poles.

Example (225 A frame, Normal interrupting, 100 A setting):

UBW225N-FTU100-3A

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