Square D QO3401021 Miniature Circuit Breaker – 40A – 3 Pole – 240V – Plug-In – Shunt Trip – QO Series

The Square D QO3401021 is a QO-series three-pole miniature circuit breaker designed for reliable overcurrent protection in residential, commercial, and light industrial 240VAC distribution systems. It features thermal magnetic protection combined with an integrated 120/208/240VAC shunt trip function, enabling remote tripping for safety or control system integration. This breaker is commonly used in QO load centers, NQ/NQOD panelboards, and OEM distribution equipment.

Electrical Ratings

• Current Rating: 40 A
• Voltage Rating: 240 VAC
• Frequency: 50/60 Hz
• Phase: 3 Phase
• Poles: 3 Pole
• Interrupting Rating: 10 kA @ 240 VAC

Protection and Function

• Trip Technology: Thermal Magnetic
• Trip Function: Common Trip (Overload + Short-Circuit Protection)
• Protection Type: Branch circuit protection
• Additional Function: AC Shunt Trip (120/208/240VAC)
• Application: Industrial, commercial, and control system distribution

Configuration and Function

• Series: QO Series (Square D / Schneider Electric)
• Model: QO3401021
• Catalog Number: QO3401021
• Frame Type: QO Miniature Frame
• Mounting Style: Plug-On
• Terminal Type: Box Lug
• Compatibility: QO Load Centers, NQOD Panelboards, OEM interiors / Speed-D switchboards

Mechanical and Physical Characteristics

• Compact molded breaker housing
• Plug-on installation for QO system compatibility
• Integrated AC shunt trip coil for remote operation
• Box lug terminals for secure conductor termination
• Designed for three-phase distribution systems
• Wire range: 8 AWG to 2 AWG (Aluminum/Copper)
• Standard QO-frame compact design

Standards and Certifications

• UL Listed
• CSA Certified
• Manufactured by Schneider Electric / Square D
• Designed for North American electrical distribution standards

Returns are easy

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

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