Eaton PXL-B40/3 40A 3-Pole B-Characteristic Miniature Circuit Breaker (MCB)

For three-phase circuits demanding reliable protection with a balanced magnetic trip, the Eaton PXL-B40/3 stands out by pairing a 40 A thermal rating with a B-characteristic curve—ideal for installations where moderate inrush currents must not cause nuisance tripping, yet short-circuit faults require immediate interruption. Its 10 kA breaking capacity and energy-limiting class 3 design ensure robust performance in residential, commercial, and light industrial distribution boards.

Highlights

• 40 A rated current, 3-pole (3P) configuration for three-phase systems
• Type B tripping characteristic: magnetic trip between 3 and 5 times rated current
• 10 kA rated breaking capacity per IEC/EN 60898-1
• Energy limiting class 3 for superior downstream protection
• DIN rail mounting (35 mm) with screw terminals for conductors up to 35 mm² rigid
• Compact 3-module width (52.5 mm) saves space in distribution boards
• IP20 terminals, IP40 front face; operating temperature -25 °C to +75 °C

In daily use

Installation is straightforward: snap the device onto a standard 35 mm DIN rail, connect line and load conductors to the clearly marked screw terminals, and torque to specification. The toggle lever provides clear ON/OFF indication and manual switching. In the event of an overload or short circuit, the PXL-B40/3 trips rapidly, protecting cables and equipment. Its high mechanical endurance (over 20,000 operations) and electrical endurance (over 10,000 operations) ensure long service life even with frequent switching. The B-curve is particularly suited for circuits with low inrush currents, such as lighting, socket outlets, and control circuits, where a C-curve might be too slow to respond to a fault.

Full specifications

• Rated current: 40 A
• Number of poles: 3
• Tripping characteristic: Type B (magnetic trip 3–5 × In)
• Rated voltage: 400 V AC
• Rated breaking capacity: 10 kA (IEC/EN 60898-1)
• Frequency: 50/60 Hz
• Mounting: DIN rail (EN 60715, 35 mm)
• Energy limiting class: 3
• Standards: IEC/EN 60898-1
• Terminal capacity (rigid): 1–35 mm²
• Terminal capacity (flexible): 1–25 mm²
• Degree of protection: IP20 (terminals), IP40 (front)
• Operating temperature: -25 °C to +75 °C
• Overvoltage category: III
• Pollution degree: 2
• Mechanical life: >20,000 operations
• Electrical life: >10,000 operations
• Module width: 3 modules (52.5 mm)
• Connection type: Screw terminals

Final note

With its proven Eaton quality, the PXL-B40/3 is a dependable choice for protecting three-phase circuits. Its combination of 40 A capacity, B-curve, and 10 kA breaking capacity makes it suitable for a wide range of applications, from residential sub-distribution to commercial panelboards. For projects requiring compliance with IEC/EN 60898-1 and a compact footprint, this MCB delivers consistent performance and peace of mind.