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Littelfuse ALT-115-S-SW - The ALT alternating relays are used to alternate between two loads. The ALT is commonly used in duplex pumping applications to balance the runtime of both pumps. The ALT-S is used in single high-level float applications. When the float switch opens, the alternating relay changes state, forcing the other pump to run the next time the float closes. All ALT relays have a built-in debounce feature that prevents the relay from changing state if the switch or float contact bounces momentarily. The ALT-X has an internal cross-connected relay and is used in dual high-level float applications. These floats are commonly referred to as lead and lag floats. The pumps alternate as in the ALT-S version but the crossconnected relay configuration allows both pumps to run simultaneously when both the lead and lag floats are closed. These relays are also available with a built-in switch (SW option) that is used to manually force one of the pumps to run every time the float switch is closed. This is helpful when a pump has been removed for repair or for test purposes. In the case of the ALT-X-SW, the switch essentially forces one pump to be the lead pump, while still allowing the second to run when both floats are closed. Must use the OT08PC socket for UL Rating!

Littelfuse ALT-115-S-SW The ALT alternating relays are used to alternate between two loads. The ALT is commonly…

Alternate Item Number: ALT115-S-SW

UPC: 079458991314


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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 ALT-115-S-SW is an 8-pin plug-in alternating relay designed for duplex pumping applications to balance runtime between two loads. This model is specifically configured for single high-level float applications, where a single float switch controls pump alternation. When the float switch opens, the relay changes state, ensuring the alternate pump operates on the next float closure. All ALT series relays incorporate a built-in debounce feature to prevent erratic switching due to momentary contact bounce from float switches or other control contacts, enhancing system reliability. The ALT-115-S-SW includes a manual override switch (SW option), allowing operators to manually force one pump to run regardless of the float switch status. This feature is particularly useful for pump maintenance, repair, or testing scenarios, ensuring continuous operation when needed. The relay operates at 115V and features DPDT (Double Pole Double Throw) contacts for versatile switching capabilities. The ALT series is ideal for applications requiring reliable load alternation and operational flexibility in fluid handling systems, such as duplex pumping setups where balanced runtime and manual override capabilities are essential.
  • Alternates between two loads for balanced runtime in duplex pumping
  • Single high-level float application configuration
  • Built-in debounce feature prevents erratic switching from contact bounce
  • Manual override switch (SW option) for forced pump operation
  • 115V AC operation, DPDT contact configuration

Specifications

Brand Name
Littelfuse
Connection Type
Screw Terminal (with OT08PC socket for UL Rating)
Mounting
DIN rail or surface mount (plug into OT08-PC socket)
Number Of Poles
DIN rail or surface mount (plug into OT08-PC socket)
Operating Temperature
-40 to 158
Operating Temperature, Maximum
158
Operating Temperature, Minimum
-40
Pickup Voltage
95-125 V
Series
ALT
Special Features
5YR WARR
Standard
UL/CSA
Sub Brand
Symcom
Voltage Rating
115 V
Package Dimensions (L x W x H)
4.13 IN x 2.38 IN x 1.75 IN
Package Dimensions (L x W x H)
104.8 mm x 60.3 mm x 44.5 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 fuse blocks and holders designed for?

Littelfuse fuse blocks and holders are selected by OEMs and designers for their compact designs, indication features, and DIN-rail mounting flexibility.

What do POWR-BLOKS power distribution blocks provide?

POWR-BLOKS power distribution blocks offer a safe and convenient way to splice cables and manage power distribution requirements within panels and systems.

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Feeder protection relays protect circuits from overcurrent, ground faults, phase loss, overload, and other detrimental conditions.

What is the Industrial Shock-Block® GFCI designed for?

The Industrial Shock-Block® GFCI is designed for people protection in industrial facilities and meets UL Standard 943C Class C and Class D.

How do high-resistance grounding systems benefit industrial applications?

High-resistance grounding limits point-of-fault damage and eliminates arc-flash hazards and transit overvoltages associated with ground faults.

What protection do Littelfuse voltage monitors offer?

Voltage monitors provide protection against both supply line and load side faults when the motor is running.

What functions do Littelfuse timers and flashers control?

Timers and flashers delay starting and stopping loads, and control cycling and sequencing of motors, pumps, compressors, heaters, and lighting.

How do Littelfuse arc-flash protection relays enhance safety?

Arc-flash relays detect a developing arc-flash incident 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.

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.