Eaton Cutler Hammer MDLB3400 400A 3 Poles Molded Case Circuit Breaker – Bolt On – 600VAC

The Eaton Cutler-Hammer MDLB3400 molded case circuit breaker is designed to deliver dependable circuit protection for industrial and commercial electrical distribution systems. Featuring the MDLB frame style and a thermal magnetic non-interchangeable trip unit, this breaker provides reliable protection against overload and short-circuit conditions. With a continuous current rating of 400 amperes at 40°C and a 3-pole configuration, it supports AC voltages up to 600VAC and DC applications up to 250VDC. Its bolt-on mounting design ensures secure installation in compatible panelboards and switchgear, while the durable molded case construction ensures long-lasting performance in demanding environments.

Product Specifications

• Brand: Eaton / Cutler-Hammer
• Model: MDLB3400
• Breaker Type: Molded Case Circuit Breaker
• Frame Type: MDLB (M Frame Style)
• Trip Unit Type: Thermal Magnetic Non-Interchangeable Trip
• Amperage Rating: 400 Ampere
• Number of Poles: 3 Pole
• Mounting Type: Bolt-On
• Frequency: 50/60 Hz
• Standard Lug Type: Not Included / Configurable

Technical Specifications

• Thermal magnetic trip mechanism for accurate overload and short-circuit protection
• Non-interchangeable trip unit with fixed protection settings
• Durable molded case housing for industrial and commercial environments
• High interrupting capacity for enhanced fault protection
• Suitable for both AC and limited DC applications
• Designed for dependable performance in heavy-duty electrical systems

Voltage and Ratings

• Maximum AC Voltage: 600 VAC
• Maximum DC Voltage: 250 VDC
• Interrupting Capacity:
• • 65 kA @ 240 VAC
  • 50 kA @ 480 VAC
  • 25 kA @ 600 VAC
  • 22 kA @ 250 VDC
• Trip Setting: 5–10 times the continuous ampere rating

Product Data

• Manufacturer: Eaton / Cutler-Hammer
• Product Series: MDLB Frame Series
• Configuration: Molded Case Circuit Breaker
• Connection Type: Bolt-On
• Warranty: 1 Year
• Application: Industrial power distribution, panelboard protection, and heavy-duty electrical circuit protection

Important Note

The product image shown represents a base model and is intended for identification purposes only. Accessories ordered with the breaker can be installed to meet your specific configuration requirements at no additional cost. Please include all required configuration details in the order comment box during checkout to ensure accurate assembly and delivery.

Returns are easy

You may return items within 10 days of delivery for a refund.

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