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Used Square D Miniature Circuit Breakers (Mcb) in Missouri, USA

  • Trusted Seller
    Square D QO230 30 A

    Square D QO230 30 A Miniature Circuit Breaker 785901400424

    • Manufacturer: Square D
    • Model: QO230

    “Item is brand new and pulled from the box.” The Square D QO230 is a 2 Pole thermal magnetic molded case circuit breaker with a current rating of 30 Amps and a voltage rating of 120/240VAC. It has an interrupting...

    $22 USD
    Latham, MO
  • Trusted Seller
    Square D QOB360VH 60 A

    Square D QOB360VH 60 A Miniature Circuit Breaker 785901054832

    • Manufacturer: Square D

    “The breaker is a pull of from a complete panel. It has sat in a warehouse for a while. Will have scratches, dust, and some adhesive” The Square D QOB360VH 60 A Miniature Circuit Breaker is a reliable and efficie...

    $35 USD
    Latham, MO
  • Trusted Seller
    square d qob130vh breaker

    square d qob130vh breaker

    • Manufacturer: Square D

    “New old stock. Will have some dust on it but never used” The Square D QOB130VH breaker is a single-pole miniature circuit breaker suitable for interior use. With a voltage rating of 120/240 Vac, this breaker is ...

    $20 USD
    Latham, MO

Overview

Miniature circuit breakers (MCBs) are compact protective switches that interrupt electrical flow in low‑voltage circuits when overloads or short circuits occur. Widely used in residential, commercial and light industrial panels, they offer resettable protection and come in single‑ to multi‑pole versions, various current ratings, breaking capacities and trip curves. MCBs typically mount on DIN rails and use thermal‑magnetic mechanisms; select units that match local standards, busbar size and application requirements.

FAQ

What should I check when buying an MCB?

Verify the nominal current (In), breaking capacity (kA), trip curve (B, C, D), number of poles, mounting type (DIN rail), and compliance with local standards (IEC/UL). Check physical condition, brand reputation and whether spare parts or datasheets are available.

How should MCBs be packed and shipped safely?

Ship in original or padded boxes to protect terminals and housing. Secure against moisture and vibration, label fragile electrical components, and use a carrier familiar with electrical goods. Include compliance certificates for customs if shipping internationally.

What routine maintenance or testing do MCBs need?

Perform visual inspections, tighten terminal connections to torque specs, cycle switches periodically, and conduct insulation and trip tests with appropriate equipment. Replace units showing overheating, physical damage, or inconsistent trips.