MJA36400 - 400 Amp Circuit Breaker

MJA36400 - 400 Amp Circuit Breaker

For the MJA36400, the 400-amp rating is only the starting point. This 3-pole circuit breaker combines a 600VAC rated operational voltage, an ET 1.0 basic electronic trip unit, and an I-Line line-side connection with mechanical load-side lugs. This combination of your electrical ratings, trip characteristics, connections, and dimensions makes the MJA36400 easier to evaluate for compatibility with existing or legacy distribution equipment. Its solid construction is built to last when correctly selected, installed, operated, and maintained for its intended electrical application.

Key Features and Benefits

• 400 Amp, 3-Pole Configuration: Provides the exact current and pole information buyers and technicians need when checking a replacement application.
• ET 1.0 Electronic Trip Unit: The MJA36400 uses a basic electronic trip unit with a specified 300–800A long-time pickup adjustment range.
• 600VAC Rating: Rated for 600VAC, 50/60Hz under UL 489, an important specification when confirming system compatibility.
• I-Line Connection: The breaker uses an I-Line connection on the line side and mechanical lugs on the load side.
• 80% Continuous Current Rating: Carries the manufacturer's stated 80% continuous current rating with an ABC phase connection.
• Push-to-Trip Function: An integral push-to-trip button provides a straightforward way to manually trip the circuit breaker.
• Load-Side Conductor Range: Specified for 3 x 3/0 AWG through 3 x 500 kcmil aluminum/copper conductors with the identified load-side terminal.

Technical Specifications

• Catalog Number: MJA36400
  
• Product Type: Circuit Breaker
  
• Device Application: Distribution
  
• Rated Current: 400A
  
• Number of Poles: 3
  
• Rated Operational Voltage: 600VAC, 50/60Hz, UL 489
  
• Network Frequency: 50/60Hz
  
• Trip Unit: ET 1.0
  
• Trip Unit Technology: Basic Electronic
  
• Long-Time Pickup Adjustment Range: 300–800A
  
• Magnetic Tripping Current: 800–4000A
  
• Continuous Current Rating: 80%
  
• Phase Connection: ABC
  
• UL 489 AIR: 100kA @ 240VAC; 65kA @ 480VAC; 25kA @ 600VAC
  
• IEC 60947-2 Icu: 65kA @ 240VAC; 50kA @ 380/415VAC
  
• IEC 60947-2 Ics: 35kA @ 240VAC; 25kA @ 380/415VAC
  
• Rated Impulse Withstand Voltage (Uimp): 8kV
  
• Line-Side Connection: I-Line Connection
  
• Load-Side Connection: Lugs
  
• Height: 12.86 in (326.64 mm)
  
• Width: 8.27 in (210.06 mm)
  
• Depth: 8.05 in (204.47 mm)
  
• Net Weight: 29 lb (13.2 kg)
  

Material Compliance and Certifications

The MJA36400 carries documented UL, CSA, and NOM product certifications and is CE-marked. Applicable standards listed in the manufacturer data include UL, CSA, NEMA, NOM-003-SCFI-2000, and IEC 60947-2. The supplied specifications also identify an IP40 degree of protection, Pollution Degree 3 per IEC 60947-1, and an HACR-rated circuit breaker application.

Where It Works Best

The MJA36400 400 amp circuit breaker is a practical form, fit, and functional replacement candidate for compatible electrical distribution equipment that calls for a 400A, 3-pole, 600VAC breaker with an I-Line configuration and ET 1.0 electronic trip unit. The I-Line line-side connection, load-side lugs, 80% continuous current rating, and defined electronic trip characteristics are all important parts of the compatibility check.