WEG UMBW-4D2-8 - MINI CIRCUIT BREAKER UMBW-4D2-8
WEG

UMBW-4D2-8

Alternate Item Number: 14363204

UPC: 7909492438168

Contact for Pricing

Overview

The WEG UMBW-4D2-8 Mini Circuit Breaker (MCB) is a compact, high-performance protective device engineered for industrial electrical systems requiring precise overcurrent and short-circuit protection. Designed to safeguard critical infrastructure, this miniature circuit breaker combines thermal and magnetic trip mechanisms to deliver comprehensive defense against overloads and fault conditions. As a trusted component in WEG’s extensive portfolio of industrial electrical solutions, the UMBW-4D2-8 exemplifies reliability, precision, and durability—qualities essential for modern power distribution, motor control, and automation environments. Miniature circuit breakers like the UMBW-4D2-8 are the first line of defense in branch circuit protection, offering rapid response to fault conditions to prevent equipment damage, electrical fires, and system downtime. The thermal trip element responds to sustained overloads by disconnecting the circuit when current exceeds rated levels for an extended period, while the magnetic trip provides instantaneous protection against short circuits, ensuring both personnel and assets remain safe. This dual-mechanism design makes the UMBW-4D2-8 ideal for protecting sensitive industrial equipment, including motors, transformers, control panels, and distribution boards. WEG, a global leader in industrial automation and electrical engineering, has designed the UMBW-4D2-8 for seamless integration into complex power systems. Its compact form factor allows for efficient installation in tight spaces, such as control cabinets, switchgear, and motor control centers, without compromising performance. The breaker’s modular design supports easy replacement and scalability, enabling system upgrades or reconfigurations with minimal downtime. Professionals across industries—including manufacturing, oil and gas, mining, water treatment, and renewable energy—rely on WEG’s MCBs to maintain operational continuity and regulatory compliance. Selecting the right miniature circuit breaker involves evaluating current rating, interrupting capacity, and application-specific requirements. The UMBW-4D2-8 is typically specified for circuits rated up to 63A, with an interrupting capacity suitable for industrial environments where fault currents can reach high levels. Its compliance with international standards (such as IEC 60898 and UL 1077) ensures compatibility with global electrical codes, making it a versatile choice for multinational projects. Installation is straightforward, with DIN rail mounting and plug-in terminals for quick, tool-free connection—ideal for time-sensitive industrial deployments. Beyond protection, the UMBW-4D2-8 enhances system reliability by reducing nuisance tripping through calibrated trip curves. This precision allows engineers to tailor protection levels to specific loads, whether protecting a single motor starter or an entire distribution panel. WEG’s reputation for engineering excellence and customer support further solidifies the UMBW-4D2-8 as a go-to solution for professionals who demand uncompromising quality. With decades of experience in industrial electrical systems, WEG delivers not just a product, but a trusted partner in maintaining safe, efficient, and resilient power infrastructure.
  • Dual thermal and magnetic trip mechanisms for overload and short-circuit protection
  • Compact design for space-efficient installation in control panels and switchgear
  • DIN rail mounting with plug-in terminals for quick, tool-free installation
  • Compliant with IEC 60898 and UL 1077 standards for global applications
  • Trusted WEG engineering for reliable protection in industrial power systems

Specifications

Package Weight (Imperial)
0.7 LB
Ground Lug

DNGL

Ground Lug
COVER,SET,AP-400,MC-265a~400a

64611614007

COVER,SET,AP-400,MC-265a~400a
INTERLOCK UNIT,AR-12M(SEPERATE),GMC(D)-6~16M

83411621001

INTERLOCK UNIT,AR-12M(SEPERATE),GMC(D)-6~16M
JB5-2 2 POLE JUMPER 5.2MM SPACING

1SNK905302R0000

JB5-2 2 POLE JUMPER 5.2MM SPACING
JB5-5 5 POLE JUMPER 5.2MM SPACING

1SNK905305R0000

JB5-5 5 POLE JUMPER 5.2MM SPACING
One-hole, metric conductor, standard barrel with window lug, 4-6mm wire, M8 stud hole.

LCMA6-8-C

One-hole, metric conductor, standard barrel with window lug, 4-6mm wire, M8 stud hole.

Frequently Asked Questions about WEG

What certifications and standards do WEG products comply with?

WEG products meet extensive international standards across multiple critical categories, including safety, electromagnetic compatibility (EMC), functional safety, and regulatory compliance. Key certifications include UL, cUL, CE, TÜV Rheinland, and compliance with international standards such as EN 61800 series, IEC 61508, ISO 13849-1, and directives like Low Voltage (2014/35/EU), EMC (2014/30/EU), and RoHS. Their products are certified for safe operation in various industrial environments, with specific standards covering electrical safety, thermal performance, electromagnetic immunity, and environmental protection.

What is WEG's warranty policy?

WEG offers an 18-month standard warranty for automation products, covering defects in workmanship and materials. The warranty requires proper transportation, handling, storage, and installation within specified environmental conditions. Repairs must be performed by authorized WEG service, and the warranty is limited to the replacement or repair of the product itself, excluding consequential damages. Extended warranty options are available, including purchasing additional coverage at 2.5% of the product's selling price per year, up to 4 additional years.

What industries and applications are WEG products used for?

WEG products are extensively used across multiple industrial sectors, including packaging equipment, material handling, food processing, pumps, medical/lab equipment, door/gate openers, office machinery, and lawn/garden applications. Their versatile DC motors and variable frequency drives (VFDs) are designed for general industrial use, with solutions ranging from off-the-shelf products to custom OEM designs that meet UL/CSA standards for diverse manufacturing and processing environments.

What technical support does WEG offer?

WEG offers comprehensive technical support through multiple channels, including a dedicated Automation Service Department accessible via toll-free phone (1-877-934-3748) and email ([email protected]). They maintain a global network of accredited service centers worldwide, which customers can locate on their website. Additionally, WEG provides warranty support and technical assistance for their industrial automation products, with pre-approval required for warranty repairs.

What are the key features of WEG products?

WEG products feature advanced industrial automation technologies with key characteristics including high performance, flexibility, and connectivity. Their flagship CFW900 Variable Speed Drive demonstrates core product strengths: intelligent thermal management, built-in safety functions, IoT readiness, advanced energy saving capabilities, and comprehensive communication protocols. WEG drives offer robust performance with features like 150% overload capacity, modern graphic HMI, plug-and-play expansion modules, and compatibility across multiple industrial segments including food and beverage, pulp and paper, and manufacturing.

What communication protocols do WEG products support?

WEG products support multiple industrial communication protocols across their product lines, including EtherNet/IP, Modbus-TCP, Modbus-RTU, CANopen, and optional protocols like Profibus-DP and DeviceNet. Specifically, the PLC500 offers 2x Gigabit Ethernet Ports, 1x CAN Port, and 1x RS485 port, enabling seamless integration with major industrial communication networks.

What environmental ratings do WEG products have?

WEG products feature multiple environmental ratings and protection classes. They offer Protection Class 3C2 as a standard coating and Protection Class 3C3 as an optional extra coating, both compliant with IEC 60721-3-3. Environmental specifications include air relative humidity from 5% to 95% non-condensing, altitude ratings up to 1,000m standard (with current derating above that), and Pollution Degree 2 classification with non-conductive pollution requirements.

What accessories are available for WEG products?

WEG offers a comprehensive range of accessories across multiple product lines. For variable frequency drives like the CFW900, accessories include I/O expansion modules, communication modules, encoder modules, temperature transducer modules, relay output modules, and HMI accessories. These accessories expand communication capabilities, input/output functions, and application flexibility. Most accessories are interchangeable between drive frames and can be installed in backplane slots, with communication network accessories limited to one per variable speed drive.

What are the main product lines offered by WEG?

WEG offers a comprehensive range of industrial automation products, including variable frequency drives (CFW series like CFW100, CFW300, CFW500), soft starters (SSW series including SSW05, SSW07, SSW900), and the innovative Motion Fleet Management (MFM) system for predictive maintenance and asset monitoring. Their product lines are designed to support industrial automation needs across various sectors, providing solutions for motor control, fleet management, and operational efficiency.

How are WEG products typically installed?

WEG products are typically installed with careful attention to mounting specifications, protection ratings, and airflow requirements. For variable speed drives like the CFW900, installation methods include surface mounting, flange mounting, and side-by-side configurations with specific clearance guidelines. Installers must follow precise dimensional requirements for each product frame size, ensuring proper ventilation and electrical connections.