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Square D KC342501021 Molded Case Circuit Breaker

  • 250A
  • 3 Pole
  • I-Line
Square D KC342501021
Molded Case Circuit Breaker
Brand Square D
SKU KC342501021
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  • 250A
  • 3 Pole
  • I-Line

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Square D KC342501021 - 250A 3 Pole Molded Case Circuit Breaker

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$6,520.59 In Stock

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Description

Designed with integrated remote tripping capabilities, this 250A molded case circuit breaker includes a factory-installed shunt trip mechanism. The unit mounts into Square D I-Line panelboards, providing extra-high interrupting capacity for demanding commercial environments. Delivering 65kAIC at 480VAC, it utilizes reliable thermal-magnetic trip technology to safeguard critical circuits. Facilities upgrading their infrastructure often transition to the PowerPact JJA36250SA.

Specifications

Key specifications
Brand Square D
Series KC
Amperage 250A
Poles 3
Mounting Style I-Line
Voltage 240VAC, 480Y/277VAC, 480VAC
Phase 3
AIC Rating 100kA @ 240VAC, 65kA @ 480Y/277VAC, 65kA @ 480VAC
Fit and installation
Frame Type KC_
Terminal Type Lugs
For Use With Square D I-Line Panelboards and Switchboards
Wire Gauge 4 AWG - 350 kcmil (Al/Cu)
Max Wire 350 kcmil
Min Wire 4 AWG
Protection and operation
Trip Technology Thermal Magnetic
Trip Function Code LI
Trip Function Long-Time, Instantaneous
Trip Adjustability Fixed Thermal, Adjustable Magnetic
Standards and features
Available Options Auxiliary Switch, Alarm Switch, Undervoltage Release
Accessories Load Side Lugs Included, Shunt Trip (Factory Installed)
Standards CSA C22.2 No. 5, IEC 60947-2, NEMA AB 1, UL 489
Approval CE, CSA, HACR, NOM, UL
Temp Rating 40C
Construction Features HACR Rated, Extra High Interrupting Capacity

Product FAQs

6 answers
What does the "1021" suffix indicate in the KC342501021 catalog number?

The 1021 suffix designates that this breaker is equipped with a factory-installed 120/240VAC shunt trip mechanism, which allows the breaker to be tripped remotely by an external voltage signal.

What is the modern replacement for the legacy KC342501021 breaker?

When upgrading infrastructure, engineers typically replace this legacy K-Frame breaker with the modern Square D PowerPact JJA36250SA, which provides the equivalent 250A rating, I-Line mounting, and integrated shunt trip functionality.

Can the KC342501021 be installed in standard Square D load centers?

No, this breaker features an I-Line style plug-in connection and is designed exclusively for commercial and industrial Square D I-Line panelboards and switchboards, not residential QO or Homeline load centers.

Does the KC342501021 require a separate mounting hardware kit for installation?

No, as an I-Line style plug-in breaker, it mounts directly onto the I-Line bus assembly in compatible panelboards and switchboards without the need for separate bolt-on mounting hardware or cable connections on the line side.

How does the adjustable magnetic trip function work on the KC342501021?

While the thermal (long-time) protection is fixed at 250 amps, the magnetic (instantaneous) trip setting is adjustable. This allows electricians to fine-tune the short-circuit response threshold to coordinate with other protective devices in the electrical system.

What is the purpose of the Push-to-Trip button on the KC342501021?

The Push-to-Trip button allows operators to manually trip the breaker to exercise and verify the mechanical operation of the tripping mechanism without exposing themselves to live electrical parts.

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Reviews

5.0
Rated 5.0 out of 5 stars
Based on 1 review
Total 5 star reviews: 1 Total 4 star reviews: 0 Total 3 star reviews: 0 Total 2 star reviews: 0 Total 1 star reviews: 0
Rating
Ratings
1 review
  • TD
    Tammy D.
    Verified Buyer
    Reviewing
    Square D KC34200 - 200A 3 Pole Molded Case Circuit Breaker
    I recommend this product
    Rated 5 out of 5 stars
    7/9/26
    Breakers

    great service!! I had bought 3 different breakers & there was one that i had to return. I called as soon as i realized it was wrong.( my fault) I had my return RMA in about 5 minutes of the phone call. Highly recommend!!