Littelfuse SE-325EN - SE-325EN is a neutral-grounding resistor monitor with a supply voltage of 240 ac and a ground-fault trip level of 0.5–4.0 A.
Littelfuse

SE-325EN

Alternate Item Number: SE-325EN

UPC: 079458988178


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Overview

The **Littelfuse SE-325EN neutral-grounding resistor monitor** is a high-precision protection device engineered for industrial power systems requiring reliable ground-fault detection. Designed to operate with a **240 VAC supply voltage**, this monitor provides adjustable ground-fault trip levels from **0.5 A to 4.0 A**, ensuring optimal sensitivity for diverse applications. Built to meet stringent industrial standards, the SE-325EN delivers consistent performance in environments where equipment integrity and operational safety are critical. Ground-fault detection is essential in medium-voltage and low-voltage power distribution systems to prevent catastrophic failures, equipment damage, and safety hazards. The SE-325EN addresses this need by continuously monitoring neutral-grounding resistor (NGR) circuits, detecting ground faults early, and enabling rapid response to mitigate risks. Its **adjustable trip settings** allow engineers to tailor sensitivity based on system requirements, balancing protection with operational continuity. **Key applications** for the SE-325EN include: - **Industrial power distribution systems** (manufacturing plants, refineries, chemical processing) - **Data centers and critical infrastructure** where uptime is non-negotiable - **Renewable energy installations** (wind, solar) with grounded systems - **Commercial buildings and hospitals** requiring high-reliability grounding - **Motor control centers and variable frequency drives (VFDs)** prone to ground faults Professionals select neutral-grounding resistor monitors like the SE-325EN based on several factors: - **Trip level adjustability** to match system impedance and fault current expectations - **Supply voltage compatibility** (240 VAC in this case) for seamless integration - **Robust construction** to withstand harsh industrial environments - **Compliance with industry standards** (e.g., IEEE, NEC, UL) for safety and reliability - **Manufacturer reputation** for durability and technical support Littelfuse, a global leader in circuit protection, surge protection, and sensing technologies, brings decades of expertise to its grounding and monitoring solutions. The SE-325EN reflects the company’s commitment to innovation, quality, and customer-centric design. With a **UNSPSC code of 39122331**, this monitor aligns with standardized procurement categories for grounding equipment, ensuring compatibility with enterprise purchasing systems. Installation of the SE-325EN is straightforward for qualified electricians, typically involving: - Mounting near the neutral-grounding resistor in the switchgear or control panel - Connecting to the 240 VAC power supply and monitoring circuits - Configuring the trip level based on system calculations (e.g., using the formula: Trip Level = System Voltage / (3 × Neutral-Grounding Resistor Value)) - Integrating with alarm systems or SCADA for remote monitoring and alerts The monitor’s **compact design** and **clear status indicators** simplify commissioning and maintenance. For systems where ground faults can escalate into arc flash events or equipment burnout, the SE-325EN provides an early warning mechanism, reducing unplanned downtime and repair costs. Its **low maintenance requirements** and **long operational lifespan** make it a cost-effective choice for both new installations and retrofits. In summary, the **Littelfuse SE-325EN** is more than a monitoring device—it’s a critical layer of protection for industrial electrical systems. Whether safeguarding sensitive electronics, preventing fires in hazardous locations, or ensuring compliance with safety regulations, this monitor delivers the precision and reliability that engineers and facility managers demand. Trusted by industries worldwide, Littelfuse’s SE-325EN sets the standard for neutral-grounding resistor monitoring in modern power systems.
  • 240 VAC supply voltage compatibility for seamless integration
  • Adjustable ground-fault trip levels from 0.5 A to 4.0 A for customized protection
  • Continuous monitoring of neutral-grounding resistor (NGR) circuits
  • Robust design for harsh industrial environments and long-term reliability
  • Compliance with industry standards (IEEE, NEC, UL) for safety and performance

Specifications

Application
Mining
Brand Name
Littelfuse
Current Rating
0.5–4.0 A
Special Features
Continuous NGR monitoring
Sub Brand
SE 325 Series
Type
Trailing Cable Protection
Voltage Rating
240 Vac
Package Weight (Imperial)
1.980 L
Package Weight (Metric)
0.900 kg
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Frequently Asked Questions about Littelfuse

What certifications and standards do Littelfuse products comply with?

Littelfuse products are certified to multiple international standards, including UL (Underwriters Laboratories), CSA (Canadian Standards Association), CCC (China Compulsory Certification), and EAC (Eurasian Conformity). Customers can verify specific product certifications by consulting individual product datasheets on Littelfuse.com, which provide comprehensive details about standards compliance for each component.

What industries and applications are Littelfuse products used for?

Littelfuse products are critical for electrical protection and safety across multiple industrial sectors, including manufacturing, automation, power distribution, and electrical control systems. Their comprehensive product portfolio serves industries that require robust electrical protection, including motor and pump applications, solar installations, programmable logic controllers (PLCs), electrical switch panels, and critical infrastructure environments. Key product lines protect against overcurrent, voltage transients, ground faults, and temperature-related electrical risks, ensuring equipment safety and operational reliability.

What technical support does Littelfuse offer?

Littelfuse offers comprehensive technical support through multiple channels. Their Technical Hotline (800-TEC-FUSE) provides direct access to engineers who can help identify issues and recommend solutions. Additionally, Littelfuse offers extensive online Technical Resources at Littelfuse.com, including datasheets, product manuals, whitepapers, application guides, and online design tools. Their experienced product and application engineers also provide step-by-step support from design to installation.

What are the main product lines offered by Littelfuse?

Littelfuse offers comprehensive industrial protection and control product lines, including fuses, fuse holders, protection relays, temperature sensors, and electrical safety components. Their key product categories span surge protective devices, custom OEM products, electrical switch panels, medium voltage fuses, ground-fault protection relays, motor and pump protection devices, and temperature sensors. These products are designed to minimize electrical safety hazards, limit equipment damage, improve productivity, and safeguard personnel from electrical faults.

What are the key features of Littelfuse products?

Littelfuse products feature exceptional circuit protection technologies with key characteristics including UL/IEC safety standard compliance, low internal resistance, and advanced protective capabilities across multiple product lines. Their components provide critical protection for industrial systems, offering features like overcurrent protection, voltage transient suppression, and resettable protection devices with ultra-low resistance and compact designs. Key product lines include fuses, metal oxide varistors (MOVs), TVS diodes, PolySwitch devices, and specialized electronic protection components that enhance system reliability and safety.

What environmental ratings do Littelfuse products have?

Littelfuse products feature comprehensive environmental ratings, including NEMA Type 1, 2, 3, 3R, 4/4X, 12, and 13 certifications, as well as IP65 protection. These ratings ensure superior protection in diverse industrial environments, with an operating temperature range of -40°F to +131°F (-40°C to +55°C). Many products also include UV-stabilized materials and neoprene gaskets for enhanced durability in outdoor and challenging conditions.

What accessories are available for Littelfuse products?

Littelfuse offers several key accessories across their product lines, including fuse holders, voltage monitoring modules, and terminal connectors. Specific accessories include the LPSM003ZXID (indicating) and LPSM003Z (non-indicating) POWR-SAFE Dead Front fuse holders for Class CC and Midget-Style fuses, the VRM6048 voltage monitor accessory module, and female quick connect terminals (P1015 series) in various wire gauge sizes. These accessories are designed to enhance protection, monitoring, and connectivity for Littelfuse electrical components.

What is Littelfuse's warranty policy?

Littelfuse provides comprehensive warranty details on their official website at www.littelfuse.com/warranty. Customers should visit this page to review the specific warranty terms and conditions for their specific product lines. For direct warranty support or questions, customers can contact Littelfuse Technical Support at 1-800-TEC-FUSE or email [email protected].

What communication protocols do Littelfuse products support?

Littelfuse supports a comprehensive range of industrial communication protocols, including PROFIBUS, PROFINET, EtherNet/IP, DeviceNet, Modbus RTU, and CANopen. Our products provide flexible connectivity solutions across multiple industrial automation platforms, enabling seamless integration with various control systems and network architectures.

How are Littelfuse products typically installed?

Littelfuse products are typically installed using specialized mounting hardware like fuse holders, blocks, and panels designed for specific industrial applications. The POWR-SAFE Dead Front holders, for example, provide optimum protection for Class CC and Midget-Style fuses, supporting installations up to 600 VAC/DC. Installation often involves using precision terminals with strain relief, such as 0.25 in. female quick connect terminals, to ensure secure and safe electrical connections in industrial control systems.