WEG UMBW-4D1-8 - MINI CIRCUIT BREAKER UMBW-4D1-8
WEG

UMBW-4D1-8

Alternate Item Number: 14363096

UPC: 7909492438069

Contact for Pricing

Overview

The WEG UMBW-4D1-8 Mini Circuit Breaker (MCB) is a high-performance protective device engineered to safeguard industrial electrical circuits against overcurrent conditions, including overloads and short circuits. Designed for branch circuit protection, this miniature circuit breaker combines advanced thermal and magnetic trip mechanisms to deliver rapid, precise fault detection and interruption. The UMBW-4D1-8 is part of WEG’s trusted line of industrial protection equipment, renowned for durability, reliability, and compliance with international safety standards. Whether installed in motor control centers, distribution panels, or power distribution systems, this MCB ensures continuous operation of critical equipment while preventing catastrophic damage from electrical faults. Miniature circuit breakers like the WEG UMBW-4D1-8 are essential components in modern industrial electrical infrastructure. They provide localized protection at the circuit level, isolating faulty sections without disrupting entire systems—a critical function in facilities where uptime is paramount. The thermal trip element responds to sustained overloads by heating a bimetallic strip, causing the breaker to trip and disconnect the circuit before conductors overheat. Meanwhile, the magnetic trip element reacts instantaneously to short-circuit conditions, using an electromagnetic coil to force the breaker open within milliseconds. This dual-mechanism design ensures comprehensive protection across a wide range of fault scenarios. The UMBW-4D1-8 is particularly well-suited for industrial applications requiring compact yet robust protection solutions. Its modular design allows for easy installation in DIN rail-mounted enclosures, making it ideal for control panels, machinery protection, and auxiliary circuits in manufacturing plants, processing facilities, and commercial buildings. Professionals in electrical engineering, maintenance, and safety compliance rely on WEG’s MCBs for their consistent performance in harsh environments, including those with high vibration, temperature fluctuations, or corrosive atmospheres. With a reputation built on decades of innovation in motor control and power distribution, WEG ensures that the UMBW-4D1-8 meets stringent industry requirements, including IEC 60898 and UL 1077 certifications. Selecting the right miniature circuit breaker involves evaluating the rated current, breaking capacity, and application-specific requirements. The UMBW-4D1-8 is typically specified for circuits with currents up to 63A, though exact ratings should be confirmed against system demands. Professionals should consider the breaker’s interrupting rating (e.g., 6kA or 10kA) to match the prospective fault current of the installation, ensuring the device can safely interrupt faults without damage. Installation is straightforward, with standard 35mm DIN rail compatibility and clear labeling for phase identification. Regular maintenance includes visual inspections for signs of wear, torque checks on terminal connections, and functional testing to verify trip mechanisms. WEG’s commitment to quality extends beyond product design to include comprehensive technical support, global distribution networks, and adherence to sustainability principles. The UMBW-4D1-8 exemplifies this ethos, offering industrial operators a dependable solution for protecting valuable assets, reducing downtime, and ensuring workplace safety. By integrating this MCB into electrical systems, engineers and facility managers gain peace of mind knowing that their circuits are shielded from the most common yet destructive electrical faults—overloads and short circuits—while maintaining compliance with evolving safety regulations.
  • Dual thermal-magnetic trip mechanisms for overload and short-circuit protection
  • Compact DIN rail-mounted design for space-efficient installations
  • Compliant with IEC 60898 and UL 1077 safety standards
  • Ideal for motor circuits, distribution panels, and industrial power systems
  • WEG’s trusted reliability in harsh industrial environments

Specifications

Mounting Type
DIN Rail
Series
UMBW
Package Weight (Imperial)
0.3 LB
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.
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
Ground Lug

DNGL

Ground Lug
ZCT,LZR-030(V),EMPR,EXP

76512124011

ZCT,LZR-030(V),EMPR,EXP
INTERLOCK UNIT,AR-12M(SEPERATE),GMC(D)-6~16M

83411621001

INTERLOCK UNIT,AR-12M(SEPERATE),GMC(D)-6~16M

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.