Littelfuse SE-325NT - SE-325NT is a neutral-grounding resistor monitor with a supply voltage of 120 ac and a ground-fault trip level of 0.5–4.0 A.
Littelfuse

SE-325NT

Alternate Item Number: SE-325NT

UPC: 079458988253


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Overview

The Littelfuse SE-325NT Neutral-Grounding Resistor Monitor is a critical component for ensuring the safety and reliability of industrial electrical grounding systems. Designed by Littelfuse, a globally recognized leader in circuit protection, this monitor provides essential oversight for neutral grounding resistors (NGRs), detecting potential ground faults before they can cause significant damage or operational disruptions. With a robust supply voltage rating of 120 VAC, the SE-325NT is engineered for seamless integration into a wide array of industrial power distribution networks. At its core, the SE-325NT's primary function is to continuously monitor the integrity of the neutral grounding path. Ground faults, which occur when an unintended electrical connection is made between a phase conductor and ground, can lead to overcurrents, equipment damage, and safety hazards. By precisely measuring the current flowing through the grounding resistor, the SE-325NT can accurately identify when this current exceeds a predefined threshold, signaling a ground fault condition. This proactive detection capability is paramount in industries where continuous operation and personnel safety are non-negotiable. The adjustable ground-fault trip level, ranging from 0.5 A to 4.0 A, offers significant flexibility, allowing engineers to tailor the monitor's sensitivity to the specific requirements of their grounding system. This adjustable range ensures that the monitor can be effectively deployed in diverse applications, from smaller, less critical systems to larger, more demanding industrial setups. Properly setting the trip level is crucial for balancing sensitivity to faults with avoiding nuisance tripping due to normal system variations. Key features and benefits of the Littelfuse SE-325NT include: * **Precise Ground Fault Detection:** Accurately identifies ground faults within the specified trip level range. * **Adjustable Trip Level:** Configurable from 0.5 A to 4.0 A for application-specific sensitivity. * **Reliable 120 VAC Operation:** Designed for standard industrial power supply voltages. * **Enhanced System Safety:** Protects personnel and equipment from the damaging effects of ground faults. * **Durable Industrial Design:** Built to withstand the rigors of demanding industrial environments. * **Trusted Littelfuse Quality:** Manufactured by a leader in circuit protection solutions. Typical applications for the SE-325NT include motor control centers, switchgear, generator systems, and any industrial facility utilizing neutral grounding resistors to limit ground fault currents. Its compact form factor and straightforward installation make it an ideal choice for both new installations and retrofitting existing systems. By incorporating the Littelfuse SE-325NT into your grounding strategy, you invest in enhanced system stability, reduced downtime, and a safer working environment. The reputation of Littelfuse for producing high-quality, reliable electrical components further solidifies the SE-325NT as a dependable choice for critical infrastructure protection.
  • Littelfuse SE-325NT Neutral-Grounding Resistor Monitor
  • 120 VAC Supply Voltage
  • Adjustable Ground-Fault Trip Level: 0.5–4.0 A
  • Designed for Industrial Grounding Systems
  • Enhances System Safety and Reliability

Specifications

Application
Mining
Brand Name
Littelfuse
Current Rating
0.5-4.0 A
Series
SE-325NT
Special Features
Continuous NGR monitoring
Sub Brand
SE 325 Series
Type
Trailing Cable Protection
Voltage Rating
120 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.