Buy now BE71B4 5 THERMISTOR Bonfiglioli IE2 High Efficiency Motor B5

Product Overview: Bonfiglioli BE71B4 with B5 Flange and Thermistor

The Bonfiglioli BE71B4 is a high-efficiency asynchronous AC motor belonging to the BE Series, which complies with IE2 efficiency standards. This specific configuration features a B5 flange mounting and an integrated PTC Thermistor for advanced thermal protection. Designed for continuous duty (S1), this 4-pole motor is a reliable powerhouse for industrial applications requiring energy savings and robust performance.

Technical Specifications and Design

The BE71B4 motor is engineered with a die-cast aluminum housing, providing excellent thermal dissipation and mechanical rigidity. The inclusion of the thermistor (PTC) is critical for protecting the windings against overheating caused by overloads, high ambient temperatures, or cooling failures. When connected to a suitable control relay, it ensures the motor shuts down before permanent insulation damage occurs.

Key Characteristics

  • Efficiency Class: IE2 (High Efficiency).
  • Frame Size: 71.
  • Poles: 4-pole (approx. 1400-1450 RPM at 50Hz).
  • Mounting: B5 Flange (Large flange).
  • Protection: Integrated PTC Thermistor.
  • Enclosure Rating: IP55 (Standard industrial protection).
  • Insulation Class: F (155°C).

Operational Reliability

This motor is ideal for coupling with Bonfiglioli gearboxes (A, W, or VF series). Its IE2 compliance ensures reduced operational costs and lower CO2 emissions compared to standard efficiency motors. The B5 mounting arrangement allows for direct vertical or horizontal coupling to gear units, ensuring perfect alignment and efficient torque transmission.

Manufacturer Bonfiglioli
Power 0.37 kW (Typical for 71B4)
Duty Cycle S1 Continuous
Voltage 230/400V (Delta/Star)

Frequently Asked Questions

Why use a thermistor instead of a bimetallic switch? Thermistors provide a more precise resistance-based temperature curve, allowing the control system to react faster to gradual heat build-up.


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