Standard Compliance

• IEC 60947-1
• IEC 60947-2
• GB/T14048.1
• GB/T14048.2

Pollution Degree

The SDM3 series operates under pollution degree 3

• As defined by the standards IEC 60947-1 and IEC 60664-1 for industrial environments.

Resistance to heat and humidity

• Dry cold, dry heat, humid heat.

Environmental Temperature

The SDM3 series can work for a long time in normal conditions with temperatures between -5°C and 40°C.

• If the operating temperature goes above 40°C (or 60°C for motor protection), please refer to the temperature reduction table, or contact us for assistance.
• The storage temperature range for the SDM3 series is from -20°C to 70°C.

Altitude

• The SDM3 series is designed for installation at altitudes up to 2000m.
• For altitudes above 2000m, factors such as lower dielectric strength and air temperature drop must be considered. Please refer to the altitude reduction table, or contact us for more details

Humidity Level

During normal operation, the following conditions must be met:

• At an air temperature of 40°C, the relative humidity must not exceed 50%.
• At lower temperatures, higher humidity is allowed.
• In the wettest month, the average relative humidity can reach 90%.
• Be mindful of condensation on the product surface, as it may affect performance.

Reliable Contact Indication with Isolation

The SDM3 series circuit breakers comply with the IEC 60947-2 isolation standards:

• The isolation position corresponds to the O (OFF) position.
• The handle will show OFF only when the contacts are fully open.
• Turning the handle or using the electrical mechanism does not affect the reliability of the contact indication system.

After testing, the isolation function must ensure:

• Mechanical reliability of the contact indication system.
• No leakage current.
• Overvoltage withstand between input and output terminals.

Protection Level

• Circuit breaker body: IP20 protection level.
• When installed in a switchgear cabinet:
  • Circuit breakers with a toggle handle: IP40.
  • Circuit breakers with an electrical mechanism: IP40.