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NEB1B125B - 125 Amp Circuit Breaker

  • 125 Amp
  • 35k @ 277VAC; 85k @ 120VAC
  • 1 Pole
Circuit BreakersSKU: NEB1B125B

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NEB1B125B - 125 Amp Circuit Breaker Description

NEB1B125B - 125 Amp Circuit Breaker

The Siemens NEB1B125B is a dependable, panelboard‑mount, low-voltage circuit breaker designed to give you solid protection and performance in both residential and commercial electrical setups. Engineered for reliability, this breaker uses a thermal‑magnetic trip unit to guard against overloads and short circuits — offering peace of mind and safety for your system. Built to meet the demands of demanding installations, the NEB1B125B manages heavy current loads with ease while fitting neatly into standard panels, making it a versatile choice whether you’re wiring a home, office, or industrial site.

Key Features and Benefits

  • Dual-action protection: The integrated thermal‑magnetic trip unit combines two methods of protection: thermal for overloads and magnetic for fast-acting short-circuit response. This ensures a dependable safeguard under varying electrical loads.
  • High fault-current capacity: With a breaking capacity of 22 kAIC at 347 V and 35 kAIC at 277 V, this breaker can handle high fault currents safely, making it suitable for demanding wiring environments.
  • Flexible wiring options: Equipped with load-side lugs (TA1EG10), the NEB1B125B supports wire sizes from 8 AWG up to 1/0 AWG (CU or AL), allowing for adaptable installation in different panel configurations.
  • Compact, panel-savvy design: Its one-pole configuration and space‑efficient dimensions let you optimize panel real estate without sacrificing safety or performance.
  • User‑friendly installation: The wiring flexibility and standard panel-mount design make installation straightforward for electricians familiar with EG-frame breakers.

Technical Specifications

  • Frame Type: EG-frame
  • Trip Unit: Thermal‑Magnetic
  • Poles: Single-pole
  • Current Rating: 125 A
  • Breaking Capacity:
    • 22 kAIC @ 347 V
    • 35 kAIC @ 277 V
  • Wire Range (Load Side Lugs): 8 AWG – 1/0 AWG (Copper or Aluminum)
  • Overall Dimensions:
    • Width: 1.0 in
    • Height: 5.5 in
    • Depth: 3.0 in
  • Approx. Weight: 1.257 lb

Material Compliance and Certifications

  • UL Listed: The NEB1B125B is UL Listed, confirming that it meets rigorous safety and performance criteria required for circuit protection devices. This certification means the breaker has been tested and validated under strict standards for safe use in both residential and commercial electrical installations.

Where It Works Best

  • This 125 A panelboard-mount breaker is an excellent choice for situations where you need reliable overload and short-circuit protection, whether in a home, small business, or larger commercial facility. Its high fault-current capacity and flexible wiring range make it ideal for main or feeder circuits, branch circuits with high load demand, or any panelboard installation where dependable protection is a priority. If you’re upgrading an existing panel or building out a new electrical system, the NEB1B125B offers a balanced mix of safety, capacity, and installation flexibility.

Use of Original Equipment Manufacturer (OEM) trademarks, names, and logos is for informational and identification purposes only. This does not imply any affiliation, sponsorship, endorsement, or approval by the original equipment manufacturer. All trademarks and registered trademarks are the property of their respective owners.

Specifications

  • Width:1.0
  • Height:5.5
  • Depth:3.0
  • Poles:1
  • Amperes:125
  • A.I.C. Rating & Volts:35k @ 277VAC; 85k @ 120VAC
  • Type:NEB
  • Approx Dimensions:1.00"W x 5.50"L x 3.00"D
  • Additional Notes:40.25C, HACR rated, Molded Case Circuit Breaker, Panelboard Mount. Includes Load-Side Terminals

Returns are easy

You may return unused items within 30 days of delivery for a full refund.

FREE shipping on breaker orders over $100 and all other items with orders over $500.

CIRCUIT BREAKER SUPERSTORE® offers one to five day delivery in the United States. The variation depends on the chosen shipping speed and the warehouse location for the product(s).

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In rare circumstances, CIRCUIT BREAKER SUPERSTORE® may reserve up to 5 business days to complete shipment. Feel free to contact us if your order is time sensitive.

CIRCUIT BREAKER SUPERSTORE® provides a limited 1-year warranty on both new and reconditioned products. Rest assured, all products are authentic OEM (original equipment manufacturer).

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