Moulded Case Circuit Breaker (MCCB) – [BENLO]

Fixed Thermal & Magnetic Molded Case Circuit Breaker (MCCB) is  a common electrical protection device used to protect circuits from damage caused by overloads and short circuits. The term "fixed" refers to the non-adjustable settings of its internal tripping mechanisms.

This type of MCCB uses two different methods to trip and break the circuit when a fault is detected:
 Thermal protection (for overloads):

• Magnetic protection (for short circuits): A solenoid coil generates an electromagnetic field when a high-level current, such as a short circuit, passes through it. The strong magnetic field instantly attracts a plunger, which trips the breaker without a delay. This rapid, instantaneous response is necessary to protect against the extreme and damaging currents of a short circuit.

 

"Fixed" vs. "adjustable"

The "fixed" aspect is what differentiates this MCCB from other types, particularly those with electronic trip units.

Fixed trip units: Both the thermal (overload) and magnetic (short circuit) settings are permanently set by the manufacturer and cannot be changed.

• Adjustable trip units: Some MCCBs, often electronic or microprocessor-based, allow for user adjustment of the trip settings. This offers more flexibility for specific applications.

 

Key characteristics

• Trip settings: Cannot be adjusted.
• Applications: Suited for industrial, commercial, and residential uses, particularly in large-scale solar photovoltaic (PV) systems, where they protect main, branch, and feeder circuits.
• Advantages: As a time-tested technology, it is an economical choice for circuit protection in many standard applications where fixed settings are appropriate.
• Disadvantages: It offers less flexibility than MCCBs with adjustable electronic trip units, and its thermal trip characteristics can be affected by ambient temperature.Product variations
  
  Benlo offers several types of MCCBs to suit different requirements: 
  • Standard MCCBs
  • Adjustable MCCBs
  • Compact MCCBs
  • Isolating MCCBs