Molded case circuit breaker ratings

Molded case circuit breakers (MCCBs) are designed to interrupt electrical currents in a circuit and provide overcurrent protection. They are commonly used in industrial and commercial applications to protect electrical equipment and personnel from electrical shock and fire hazards. Here are some common ratings for molded case circuit breakers:

  1. Voltage Rating: MCCBs are available in various voltage ratings, including:
    • 120/240V AC (residential and commercial applications)
    • 277/480V AC (industrial and commercial applications)
    • 600V AC (industrial applications)
    • 690V AC (industrial applications)
  2. Current Rating: MCCBs are available in various current ratings, including:
    • 15A to 600A (residential and commercial applications)
    • 15A to 2000A (industrial applications)
  3. Interrupting Rating: This is the maximum current that the breaker can interrupt without causing damage. Interrupting ratings are typically measured in amperes (A) and are available in various ranges, including:
    • 10kA to 50kA (residential and commercial applications)
    • 50kA to 100kA (industrial applications)
  4. Short-Circuit Current Rating: This is the maximum current that the breaker can withstand for a short duration (typically 1-2 cycles) without causing damage. Short-circuit current ratings are typically measured in amperes (A) and are available in various ranges, including:
    • 10kA to 50kA (residential and commercial applications)
    • 50kA to 100kA (industrial applications)
  5. Inrush Current Rating: This is the maximum current that the breaker can withstand during the inrush current of a motor or other inductive load. Inrush current ratings are typically measured in amperes (A) and are available in various ranges, including:
    • 10A to 100A (residential and commercial applications)
    • 100A to 500A (industrial applications)
  6. Frequency Rating: MCCBs are designed to operate at specific frequencies, including:
    • 50/60Hz (residential and commercial applications)
    • 60Hz (industrial applications)
  7. Environmental Ratings: MCCBs are designed to operate in various environmental conditions, including:
    • Temperature range: -20°C to 40°C (-4°F to 104°F)
    • Humidity: 5% to 95% RH
    • Altitude: up to 2000 meters (6562 feet)
  8. Certifications: MCCBs may be certified to various standards, including:
    • UL (Underwriters Laboratories)
    • CSA (Canadian Standards Association)
    • IEC (International Electrotechnical Commission)
    • VDE (German Electrical Engineering Association)

It's important to note that the specific ratings and certifications of a molded case circuit breaker will depend on the manufacturer and the specific product. It's essential to consult the manufacturer's documentation and specifications to ensure that the breaker is suitable for your application.