MT3300T - 300 Amp Trip Unit

MT3300T - 300 Amp Trip Unit for Eaton MDL & HMDL Circuit Breakers

If you're working with Eaton MDL or HMDL circuit breakers and need a solid trip unit that gets the job done, the Eaton MT3300T is a no-brainer. Rated at 300 amps, this thermal-magnetic trip unit offers dependable circuit protection without taking up a ton of space. It’s designed to fit neatly into J-K frame breakers, making it a smart choice whether you’re upgrading an existing setup or building a new one from scratch.

Key Features and Benefits

• Reliable Protection: With thermal-magnetic trip technology, this unit reacts quickly to overloads and short circuits—helping you avoid costly downtime or damage to your system.
• Tailored Compatibility: Built specifically for Eaton’s MDL and HMDL breakers, so you know it’ll fit and function exactly how it should.
• Compact but Capable: It’s not bulky, but don’t let the size fool you—it handles 300 amps like a champ.
• Easy to Work With: Designed for professionals who want performance without the hassle. Quick to install and built to last.

Technical Specifications

• Type: Thermal-magnetic trip unit
• Amperage Rating: 300A
• Frame Compatibility: J-K frames
• Breaker Compatibility: Eaton MDL and HMDL
• Poles: 3-pole configuration
• Dimensions:
  • Depth: 7″
  • Height: 4″
  • Width: 4″
• Weight: 3 lbs
• Series: C

Material Compliance and Certifications

• This trip unit is UL Listed, so it meets the industry’s top safety and performance standards. Manufactured under Eaton’s strict quality controls, you’re getting a unit that’s been built for real-world conditions, not just a spec sheet.

Where It Works Best

• The MT3300T is right at home in commercial buildings, manufacturing plants, and institutional facilities—basically anywhere you need dependable, high-capacity circuit protection. It’s a great fit for power distribution systems that require consistent, reliable performance. Just remember: this is the trip unit only, so you’ll need a matching breaker frame to complete the setup.