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Littelfuse LSR-115 - The LSR-XXX load sensors use current levels to determine feed rates, tool wear, loss of prime on pumps, mixer viscosity and all types of overload and underload conditions. They may also be used to stage pump motors, chillers and other machinery. These devices combine a current transformer (CT) with Form C (SPDT) relay contacts to switch alarm circuits, contactors or any resistive or inductive load. One simple screwdriver adjustment will calibrate the sensor for all single-phase or 3-phase applications up to 100hp.

Littelfuse LSR-115 The LSR-XXX load sensors use current levels to determine feed rates, tool wear, loss of…

Alternate Item Number: LSR-115

UPC: 079458996661


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Contact for Pricing

Call +1 (262) 252-1600 (toll-free 877-268-3700) or email [email protected] for pricing and availability.

Overview

The Littelfuse LSR-115 Load Sensor (SKU: LSR-115) is a versatile current monitoring relay designed for precise industrial motor protection and process control. This device utilizes an integrated current transformer (CT) to accurately measure motor current, enabling the detection of critical operational parameters such as feed rates, tool wear, loss of prime on pumps, and mixer viscosity. It effectively identifies all types of overload and underload conditions, safeguarding machinery and optimizing processes. The LSR-115 is also ideal for staging pump motors, chillers, and other machinery. This load sensor combines reliable current sensing with Form C (SPDT) relay contacts, capable of switching alarm circuits, contactors, or any resistive or inductive load. The output contact rating is 480VA at 240VAC for pilot duty and 10A for general purpose applications. Calibration is simplified with a single screwdriver adjustment, making it suitable for all single-phase or 3-phase applications up to 100 horsepower (hp). Key specifications include a broad current adjustment range from 0.5A to 135A (typically 2A-100A) with an adjustable trip setpoint accuracy of ±1%. The control power for the LSR-115 is 115VAC. Functional isolation is rated at 600VAC rms. The unit features a 20-turn potentiometer for fine adjustment and status LEDs for clear operational feedback. Constructed for industrial environments, the LSR-115 operates within a temperature range of -20°C to 70°C (-4°F to 158°F). It accepts wire sizes from #12-24AWG with a terminal torque of 7 in.-lbs. The compact enclosure measures 42.42 mm (1.67”) in height, 58.42 mm (2.3”) in width, and 90.43 mm (3.56”) in depth. Mounting is achieved via four #6 screws. The Littelfuse LSR-115 is an essential component for applications requiring accurate motor current monitoring, enhancing operational efficiency and equipment longevity.
  • Monitors motor current for overload and underload conditions up to 100hp.
  • Integrated current transformer (CT) and Form C (SPDT) relay contacts.
  • Current adjustment range: 0.5A-135A (typical 2A-100A) with ±1% trip setpoint accuracy.
  • Control power: 115VAC; Isolation: 600VAC rms.
  • Compact dimensions (42.42mm H x 58.42mm W x 90.43mm D) with four #6 screw mounting.

Specifications

Brand Name
Littelfuse
Connection Type
Screw Terminal
Current Rating
0.5-135 A
Frequency
50/60 Hz
Mounting
Four #6 screws 3/4 in length
Mounting Type
Panel Mount
Number Of Poles
Four #6 screws 3/4 in length
Operating Temperature
-4 to 158
Operating Temperature, Maximum
158
Operating Temperature, Minimum
-4
Poles
Form C (SPDT)
Poles
1P+G (Form C SPDT)
Series
LSR
Size
42.42mm H x 58.42mm W x 90.43mm D
Special Features
5YR WARR
Standard
CSA/CE
Sub Brand
Symcom
Voltage Rating
115 VAC
Package Dimensions (L x W x H)
3.56 IN x 2.3 IN x 1.67 IN
Package Dimensions (L x W x H)
90.4 mm x 58.4 mm x 42.4 mm
RTXD Extractor Tool

6896057-1

RTXD Extractor Tool
Relay Accessories, Sockets & Clips, Printed Circuit Board, Phenolic, Printed Circuit Board, 6, Socket, Potter & Brumfield R10

1-1393143-3

Relay Accessories, Sockets & Clips, Printed Circuit Board, Phenolic, Printed Circuit Board, 6, Socket, Potter & Brumfield R10
Relay Accessories, Sockets & Clips, Solder, Polyester, Printed Circuit Board, 2, Socket, Potter & Brumfield R10

1-1393143-6

Relay Accessories, Sockets & Clips, Solder, Polyester, Printed Circuit Board, 2, Socket, Potter & Brumfield R10
Power supply for DIN-rail

PS-60

Power supply for DIN-rail
IP67 SCP-X Extreme Environment Series Power Supply. Double Stacked, Output Power 2 x 100W, Output Voltage 24 Vdc, Output Current 7.6 A total, 3.8 A per pair

SCP102D24X-C02

IP67 SCP-X Extreme Environment Series Power Supply. Double Stacked, Output Power 2 x 100W, Output Voltage 24 Vdc, Output Current 7.6 A total, 3.8 A per pair

Frequently Asked Questions

What types of fuses does Littelfuse offer for industrial applications?

Littelfuse offers UL Class fuses, high-speed fuses, medium voltage fuses, 10 x 38 mm fuses, and solar fuses for industrial applications.

What are Littelfuse high-speed fuses used for?

High-speed fuses protect critical power semiconductor devices against short circuits in power conversion applications like inverters and variable-speed drives.

What kind of protection do medium voltage fuses provide?

Medium voltage fuses protect transformers, potential transformers, feeders, and motor circuits, with designs available for various current, voltage, and interrupting ratings.

What are the voltage and amperage ranges for 10 x 38 mm fuses?

10 x 38 mm fuses are available with ratings from 125 to 1000 volts and 1/10 to 30 amperes.

What is the maximum voltage for Littelfuse solar fuses?

Littelfuse offers solar fuses and holders up to 1500 Vdc for both high-current and low-current applications.

What are Littelfuse arc-flash protection relays designed to do?

Arc-flash relays detect developing arc-flash incidents and send a trip signal to interrupt power before significant damage occurs.

What types of motor protection does Littelfuse provide?

Littelfuse offers voltage monitors, current monitors, and Bluetooth-enhanced overload relays for low and medium voltage motor protection applications.

What do pump controllers from Littelfuse do?

Pump controllers protect and disable a pump if a hazardous condition arises, with options available for single-phase and three-phase applications.

How do ground-fault protection relays work?

Sensitive ground-fault relays use advanced filtering to quickly detect insulation resistance breakdown caused by moisture, vibration, chemicals, or dust.

What is the Littelfuse University (LFU)?

LFU is an award-winning resource offering in-depth training courses and quick references on Littelfuse products, programs, and tools, with courses ranging from 3 to 20 minutes.

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.