
Contact for Pricing
Overview
- Universal input voltage: 24 to 240VAC, 50/60Hz
- Adjustable flash rate: 10 to 100 FPM
- Supports inductive, resistive, or incandescent loads up to 10A (100A inrush)
- Encapsulated solid-state design for durability in harsh environments
- Surface mount with #10 screw; compact 2" x 2" x 1.51" dimensions
Specifications
Series | FSU |

FS126RC
The FA and FS Series Flashers have proven their reliability through years of use on communication towers, smoke stacks, cooling towers, tall buildings, bridges and utility towers. The highest quality components are encapsulated in a rugged plastic housing with a molded-in heat transfer plate. The flash rate, ratio, and failsafe design meet FAA regulations. Zero voltage switching can increase lamp life up to ten times. The FS155-30RF & FS165-30RF include superior RF filtering circuitry for use in high RF installations, including AM hot towers. Operation: FS Series - Flasher (OFF First), FA Series - Flashers & Aux. Modules: Upon application of input voltage, the T2 OFF time begins. At the end of the OFF time, the T1 ON time begins and the load energizes. At the end of T1, T2 begins and the load de-energizes. This cycle repeats until voltage is removed. Reset: Removing input voltage resets the output and the sequence to T2.
FS127
The FA and FS Series Flashers have proven their reliability through years of use on communication towers, smoke stacks, cooling towers, tall buildings, bridges and utility towers. The highest quality components are encapsulated in a rugged plastic housing with a molded-in heat transfer plate. The flash rate, ratio, and failsafe design meet FAA regulations. Zero voltage switching can increase lamp life up to ten times. The FS155-30RF & FS165-30RF include superior RF filtering circuitry for use in high RF installations, including AM hot towers. Operation: FS Series - Flasher (OFF First), FA Series - Flashers & Aux. Modules: Upon application of input voltage, the T2 OFF time begins. At the end of the OFF time, the T1 ON time begins and the load energizes. At the end of T1, T2 begins and the load de-energizes. This cycle repeats until voltage is removed. Reset: Removing input voltage resets the output and the sequence to T2.
PCR11
The PCR Series of photo control is a combination of precision electronic circuitry, electromechanical output, and unique molded plastic housing. Designed and built to meet the demands of the most rigorous requirement of tower and obstruction lighting control, each unit is factory calibrated to meet FAA and FCC specifications. Electronic circuit, output contactor, and terminal block are all contained within front plastic housing. Edge support molded into the bottom edge of housing allows easy wiring of new and existing installations. Available with or without cast aluminum junction box. Operation: When the amount of light sensed falls below the actuation level for energization, the output relay energizes. Conversely, when the amount rises above the actuation level for de-energization, the output relay de-energizes.
FS146
The FA and FS Series Flashers have proven their reliability through years of use on communication towers, smoke stacks, cooling towers, tall buildings, bridges and utility towers. The highest quality components are encapsulated in a rugged plastic housing with a molded-in heat transfer plate. The flash rate, ratio, and failsafe design meet FAA regulations. Zero voltage switching can increase lamp life up to ten times. The FS155-30RF & FS165-30RF include superior RF filtering circuitry for use in high RF installations, including AM hot towers. Operation: FS Series - Flasher (OFF First), FA Series - Flashers & Aux. Modules: Upon application of input voltage, the T2 OFF time begins. At the end of the OFF time, the T1 ON time begins and the load energizes. At the end of T1, T2 begins and the load de-energizes. This cycle repeats until voltage is removed. Reset: Removing input voltage resets the output and the sequence to T2.Frequently Asked Questions
What voltage range does the FSU1004 support?
The FSU1004 operates on 24 to 240VAC at 50/60Hz.
What is the maximum load current for the FSU1004?
The FSU1004 supports a maximum steady-state load of 10A with an inrush current of 100A.
How do I adjust the flash rate on the FSU1004?
The flash rate is adjustable between 10 and 100 flashes per minute (FPM) using onboard controls.
What types of loads can the FSU1004 control?
The FSU1004 can control inductive, resistive, or incandescent loads.
What is the operating temperature range for the FSU1004?
The FSU1004 operates from -20°C to 60°C and stores from -40°C to 85°C.
How is the FSU1004 mounted?
The FSU1004 is surface-mounted using a single #10 (M5 x 0.8) screw.
What are the dimensions of the FSU1004?
The FSU1004 measures 2" x 2" x 1.51" (H x W x D).
Does the FSU1004 have a fixed ON/OFF ratio?
Yes, the ON/OFF ratio is approximately 50%.
What termination type does the FSU1004 use?
The FSU1004 uses 0.25 in. (6.35 mm) male quick-connect terminals.
Is the FSU1004 suitable for continuous duty operation?
Yes, the FSU1004 is designed for continuous ON/OFF recycling operation.
How to Install the Littelfuse FSU1004 Universal Adjustable Flasher
Step-by-step guide to mounting and wiring the FSU1004 flasher for industrial or automotive applications.
Estimated time: 15m
Tools needed:
Screwdriver, Wire strippers, Crimping tool
Supplies needed:
#10 mounting screw, Female quick-connect terminals (if needed), Heat sink compound (for >6A units)
- Mount the flasher
Secure the FSU1004 to a flat surface using the included #10 screw. For units rated >6A, apply heat sink compound and bolt to a metal surface with a maximum temperature of 90°C.
- Connect the input voltage
Connect the input voltage (24-240VAC) to terminal 2. Ensure polarity is correct for AC applications.
- Connect the load
Connect the load (lamp or signal) to terminal 3. Verify the load type (inductive, resistive, or incandescent) matches the flasher's specifications.
- Set the flash rate
Adjust the onboard control to set the desired flash rate between 10 and 100 FPM.
- Test the installation
Apply power and verify the flasher operates correctly. Check for proper flashing and load activation.
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.



