WEG MPW-40-3-D040 Motor Protection Circuit Breaker

The WEG MPW-40-3-D040 motor protection circuit breaker covers the 3.2 A to 4.0 A current range in the MPW-40 frame, delivering integrated thermal-magnetic protection for three-phase motors from 1.5 kW to 2.2 kW at 400 V AC. The 1.5–2.2 kW motor range is among the most common in Saudi industrial facilities, used for supply air handling unit fans, cooling water circulation pumps, small conveyor drives, compressed air system auxiliaries, and fire fighting system pump auxiliaries — all applications where reliable motor branch circuit protection is critical to plant availability and safety.

Technical Protection Performance

The MPW-40-3-D040 provides Class 10 trip time characteristics suitable for standard IEC motors with direct-on-line starting. The thermal element is phase-loss sensitive, detecting and tripping within seconds on single-phase operation. The magnetic release trips instantaneously at approximately 12× rated current, preventing arc energy accumulation in the event of a bolted short circuit at the motor terminals or starter panel busbars. The 100 kA breaking capacity at 400 V AC ensures the device can safely interrupt fault currents at the distribution board feed points in Saudi industrial LV switchboards.

DOL and Reversing Starter Assemblies

The MPW-40-3-D040 is used in both DOL and reversing starter configurations. For reversing starters — used for bi-directional conveyors, damper actuators, and positioning drives — two CWM contactors are used with mechanical and electrical interlocking, protected by the MPW-40-3-D040 as the common branch circuit protection device. WEG provides reversing starter coordination data confirming the MPW-40-3-D040 performance with CWM contactors under reverse-plugging conditions. Razz Middle East supplies complete reversing starter assemblies pre-wired and tested for Saudi industrial applications.

Saudi Aramco and SABIC Project Specifications

Saudi Aramco's General Instruction GI-2.710 for rotating machinery maintenance and SAES-P-100 for electrical system design reference IEC 60947-4-1 as the governing standard for motor protection devices. The MPW-40-3-D040 satisfies these references and is submitted to Saudi Aramco Inspection (SAI) as part of MCC package documentation. SABIC technical standard STS-0-7-1 for motor control centres similarly mandates IEC type-tested motor protection circuit breakers, which the MPW-40-3-D040 fulfils.

Available from Razz Middle East

Razz Middle East maintains local Saudi inventory of WEG MPW-40-3-D040 for immediate delivery to project sites and panel builders. Technical data sheets, type test certificates, and bill-of-materials support are provided to all project customers. Our team supports Saudi Aramco, SABIC, and SEC project procurement teams from bid stage through factory acceptance testing and site commissioning.