1SDX254921R1 ABB EPX-XT1S-TM0403 40A 3-Pole 50kA MCCB TMA

Why Choose the ABB EPX-XT1S-TM0403 40A 3-Pole 50kA MCCB?

The ABB EPX-XT1S-TM0403 is a robust 40 A three-pole moulded case circuit breaker (MCCB) designed to provide dependable overload and short-circuit protection for commercial and industrial low-voltage electrical distribution systems. Part of the ABB Protecta Power Devices range, this circuit breaker combines a 50 kA short-circuit breaking capacity with TMA adjustable thermal-magnetic protection, offering a practical solution for three-phase electrical installations requiring reliable circuit protection.

Based on the established ABB SACE Tmax XT1S platform, the EPX-XT1S-TM0403 uses a thermal-magnetic trip unit rather than an electronic release. The TMA protection system combines adjustable thermal overload protection with adjustable magnetic short-circuit protection, allowing the protective characteristics to be configured to suit the electrical circuit and connected equipment.

With its 40 A rated current, three-pole configuration and 50 kA breaking capacity, the ABB EPX-XT1S-TM0403 is suitable for appropriately designed three-phase distribution circuits in commercial buildings, industrial facilities and electrical distribution assemblies. Identified by ABB order code 1SDX254921R1, this MCCB is intended for integration into compatible ABB Protecta Power equipment.

Key Advantages

• 40 A rated current for commercial and industrial low-voltage distribution circuits.
• Three-pole (3P) configuration for coordinated switching and protection of three-phase circuits.
• 50 kA short-circuit breaking capacity for installations with substantial prospective fault currents.
• TMA thermal-magnetic protection provides overload and short-circuit protection without an electronic trip unit.
• Adjustable thermal overload protection allows the overload setting to be matched to the circuit design.
• Adjustable magnetic protection provides flexibility when configuring short-circuit trip characteristics.
• Thermal overload response helps protect conductors against sustained excessive current.
• Magnetic short-circuit response provides rapid interruption during high-current faults.
• ABB SACE Tmax XT1S construction combines compact design with dependable circuit protection.
• Mechanical thermal-magnetic operation provides a straightforward protection solution.
• Three-pole switching supports coordinated disconnection of three-phase circuits.
• Suitable for integration into compatible ABB Protecta Power distribution assemblies.
• ABB manufacturing quality supports dependable operation in professional electrical installations.

Key Features

• ABB Protecta Power Devices product group.
• EPX-XT1S-TM0403 product designation.
• 40 A rated current for low-voltage circuit protection.
• Three-pole (3P) construction for three-phase electrical distribution.
• 50 kA short-circuit breaking capacity in the specified Protecta Power configuration.
• TMA thermal-magnetic trip unit for overload and short-circuit protection.
• Adjustable thermal protection for sustained overload conditions.
• Adjustable magnetic protection for high-current short-circuit faults.
• Inverse-time thermal response helps protect conductors against prolonged overloads.
• Instantaneous magnetic response provides rapid operation during significant short-circuit faults.
• ABB SACE Tmax XT1S platform with S short-circuit performance classification.
• XT1 frame family for compact low-voltage circuit protection.
• Manual switching mechanism with automatic thermal-magnetic protective tripping.
• Robust moulded case construction suitable for commercial and industrial electrical environments.
• Three-phase circuit protection within compatible electrical distribution equipment.
• Designed for compatible ABB Protecta Power panelboards and distribution assemblies.

Adjustable Thermal-Magnetic Protection for Three-Phase Power Distribution

The ABB EPX-XT1S-TM0403 provides dependable protection for low-voltage electrical distribution circuits where a compact, adjustable thermal-magnetic circuit breaker is required. Its protection system combines a thermal element for sustained overload conditions with a magnetic element for short-circuit faults. This dual protection arrangement helps safeguard conductors, connected equipment and electrical distribution infrastructure against excessive current.

The thermal overload protection responds to current levels that exceed the configured operating threshold for a sufficient period. Its inverse-time characteristic means that higher overload currents generally produce faster operation. This helps protect electrical conductors against excessive heating while accommodating normal variations in operating current within the circuit's design limits.

The TMA trip unit provides an adjustable thermal setting, allowing electrical designers and installers to configure overload protection according to the conductor current-carrying capacity and connected load requirements. Correct selection of the thermal setting is important for maintaining appropriate protection and avoiding unnecessary interruptions during normal operation.

The magnetic short-circuit protection responds rapidly when current exceeds the selected magnetic trip threshold. Unlike a thermal-only overload response, magnetic protection is intended to interrupt high-current short-circuit faults without an intentional time delay. The adjustable magnetic setting provides additional flexibility when selecting protective characteristics for the electrical installation.

A key advantage of the TMA configuration is that both the thermal and magnetic protection thresholds can be adjusted. This distinguishes it from thermal-magnetic trip units with a fixed magnetic threshold. The TMA arrangement provides a practical balance between straightforward mechanical protection and configurable circuit protection settings, without requiring an electronic trip unit.

The ABB SACE Tmax XT1S platform provides a compact foundation for the EPX-XT1S-TM0403. Its 40 A current rating makes it suitable for appropriately designed three-phase outgoing circuits, while the specified 50 kA breaking capacity supports use in installations where higher short-circuit performance is required.

As part of the ABB Protecta Power range, this MCCB is intended for installation in compatible panelboards and distribution assemblies using the appropriate mounting and connection components. Electrical designers and installers should verify the installation's prospective fault current, operating voltage, conductor ratings, protection settings and coordination requirements before commissioning. The selected thermal and magnetic settings should be checked against the applicable ABB technical documentation.

Typical Applications

• Commercial and industrial low-voltage electrical distribution systems.
• ABB Protecta Power panelboards and compatible distribution assemblies.
• Three-phase outgoing circuit protection.
• Industrial switchboards and sub-distribution panels.
• Manufacturing and production facilities.
• Commercial offices and business premises.
• Retail buildings and hospitality facilities.
• Warehouses and logistics centres.
• Building services and mechanical plant electrical distribution.
• Distribution circuits requiring adjustable thermal overload protection.
• Electrical installations requiring adjustable magnetic short-circuit protection.
• Three-phase feeder circuits with appropriately rated conductors and connected loads.
• Electrical infrastructure upgrades, maintenance and replacement projects.