Littelfuse PSX1XLUB0350 - POWR-SPEED SQB SIZE 1XL BOLTED BL 350A. Littelfuse PSX series 1500 V dc high-speed square bodyfuses are specially designed to protect battery energy storage systems (BESS), photovoltaic inverters, and many of dc applications such as dc common bus systems, larger industrial regenerative drives, rectifiers and, metal processing equipment. The PSX series fuses are extremely fast-acting, offering high-speed performance up to 1500 V dc, ranging from 80 A to 1400 A in the smallest NH XL package sizes. The PSX series is available with multiple mounting terminations including flush-end style, DIN-style and bolted-blade style. Visual blown fuse indication is standard on all fuses and optional micro-switch is available for external indication. PSX series are certified to UL 248-13 and designed to meet EN high-speed semiconductor fuse standard and IEC 60269-7, a new battery protection fuse standard in development.
Littelfuse

PSX1XLUB0350

Alternate Item Number: PSX1XLUB0350X

UPC: 079458258271


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Overview

The Littelfuse PSX1XLUB0350 is a high-speed square body fuse designed for critical DC protection in battery energy storage systems (BESS), photovoltaic inverters, and industrial applications. Rated at 1500V DC and 350A, this Size 1XL fuse delivers ultra-fast response times (<=3ms) to safeguard high-energy DC circuits, including DC common bus systems, regenerative drives, rectifiers, and metal processing equipment. The bolted-blade termination ensures secure, low-resistance connections with a recommended tightening torque of 26Nm (M10 or 3/8" fasteners). Engineered for energy efficiency, the PSX series features low watt loss to minimize power dissipation in BESS applications while maintaining compact NH 1XL dimensions for flexible system design. Visual blown fuse indication is standard, with an optional micro-switch (MSXL2000C) for external signaling. Certified to UL 248-13 and designed to meet IEC 60269-7 (Class aBat) and EN high-speed semiconductor fuse standards, the PSX1XLUB0350 provides reliable protection with a DC interrupting rating of 250kA. Operating from -55°C to +125°C and compliant with RoHS/REACH, this fuse is manufactured in Mexico for global reliability in renewable energy and industrial environments.
  • 1500V DC voltage rating with 350A amperage for high-energy DC systems
  • Ultra-fast response time (<=3ms) for critical fault protection
  • Bolted-blade termination with 26Nm tightening torque (M10/3/8" fasteners)
  • Low watt loss design for energy efficiency in BESS applications
  • Visual blown fuse indication standard; optional micro-switch for external signaling

Specifications

Amperage Rating
350 A
Brand Name
Littelfuse
Case Size
NH 1XL
Connection Type
Bolted-Blade
Current Rating
350 A
Interrupting Rating
157 kA @ 1500 Vdc
Mounting Type
Bolted
Response Time
Very Fast-Acting (FF)
Series
PSX
Size
Size 1XL
Sub Brand
POWR-SPEED® Fuse
Type
Square Body Fuse
Voltage Rating
1500 V
Watts loss at 100% rated current
51.8 W
Fuse Block 600VAC 600VDC Class CC 30A 1/4in Quick Connect / Solder 90 angle screw Knob Panel Mount

GPM-SRR90

Fuse Block 600VAC 600VDC Class CC 30A 1/4in Quick Connect / Solder 90 angle screw Knob Panel Mount
Fuse Holder UltraSafe™ 800VAC 1000VDC UL Fuse size 14x51 1-Pole Visual Indicator Microswitch Pressure Plate IP20

C331156

Fuse Holder UltraSafe™ 800VAC 1000VDC UL Fuse size 14x51 1-Pole Visual Indicator Microswitch Pressure Plate IP20
Fuse Block 1500VAC 1500VDC 400A 1-Pole Stud M8

1SCM8

Fuse Block 1500VAC 1500VDC 400A 1-Pole Stud M8
Fuse Holder Modulostar® Size 10x38 IEC 690VAC 690VDC 3-Pole IP20

E1062696

Fuse Holder Modulostar® Size 10x38 IEC 690VAC 690VDC 3-Pole IP20
POWR-JAW clamps improve the contact between fuse and clip. The unnecessary heat from poor contact due to the loss of spring force in the clips can cause nuisance fuse opening and premature aging of surrounding components. High temperature phenolic resin knob designed for the most severe environments 7 sizes to provide effective coverage. Simple design makes installation easy.

LCC5

POWR-JAW clamps improve the contact between fuse and clip. The unnecessary heat from poor contact due to the loss of spring force in the clips can cause nuisance fuse opening and premature aging of surrounding components. High temperature phenolic resin knob designed for the most severe environments 7 sizes to provide effective coverage. Simple design makes installation easy.
9F61 Size B Clips 1.6in

9F61BWW460

9F61 Size B Clips 1.6in

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.