Littelfuse TDR4A11 - The TDR Series of time-delay relays are comprised of digital circuitry and an isolated, 10A relay output. The ON and OFF delays are selected by means of two, ten position binary switches, which allow the setting of the desired delay to be precise every time. Operation (Recycling - ON Time First): Upon application of input voltage, the green LED glows, the output relay is energized, the red LED glows, and the T1 ON time begins. At the end of the ON time, the output de-energizes, the red LED turns OFF and the T2, OFF time begins. At the end of the OFF time, the output relay energizes and the cycle repeats as long as input voltage is applied. Reset: Removing input voltage resets the output and time delays, and returns the sequence to the first delay. Operation (Recycling - OFF Time First): Upon application of input voltage, the green LED glows, the T1 OFF time begins, the load is OFF. At the end of the OFF time, the T2 ON time begins, the load energizes, and the red LED glows. At the end of the ON time the load de-energizes and the red LED turns OFF. The cycle repeats until input voltage is removed. Reset: Removing input voltage resets the output and the sequence to the OFF time.
Littelfuse

TDR4A11

Alternate Item Number: TDR4A11

UPC: 079458999808

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Overview

The Littelfuse TDR4A11 is a dedicated recycling time-delay relay engineered for precise industrial automation and process control. This unit features advanced digital integrated circuitry and an isolated 10A DPDT relay output, delivering highly accurate ON and OFF delay timing. The TDR4A11 utilizes two ten-position binary switches for exact delay settings, ensuring repeatable performance with a setting accuracy of ±2% or 50ms (whichever is greater). The repeat accuracy is rated at ±0.1% or 20ms (whichever is greater), guaranteeing consistent operation. Operating on 120VAC input with a tolerance of -20% to +10%, this relay consumes a maximum of 3.25W. It supports two distinct recycling modes: ON Time First and OFF Time First, offering flexibility in load sequencing and application design. The time delay range is precisely adjustable from 0.1 to 102.3 seconds in 0.1-second increments, with other TDR Series models available for extended ranges. Visual status indication is provided by a green LED for input voltage presence and a red LED for output relay energization. The isolated DPDT electromechanical relay contacts are rated for 10A resistive at 120/240VAC and 28VDC, and can handle 1/3 hp at 120/240VAC. The maximum switching voltage is 250VAC. The relay boasts a substantial mechanical life of 1 x 10^7 operations and an electrical life of 1 x 10^6 operations. Input-to-output isolation is rated at ≥1500V RMS. Mechanically, the TDR4A11 is designed for plug-in socket mounting with an octal 8-pin termination. Its compact dimensions are 81.3mm (H) x 60.7mm (W) x 45.2mm (D). The operating temperature range is -20°C to 65°C. This relay is an ideal choice for applications requiring reliable, cyclical timing control in industrial machinery, control panels, and automated systems where precise and repeatable timing is critical.
  • Digital integrated circuitry for precise timing
  • Adjustable ON and OFF delays from 0.1 to 102.3 seconds
  • Two ten-position binary switches for exact settings
  • Isolated 10A DPDT electromechanical relay output
  • 120VAC input with LED status indicators (Green for input, Red for output)

Specifications

Brand Name
Littelfuse
Color
Green, Red
Connection Type
Octal 8-pin plug-in socket
Current Rating
10 A
Frequency
50/60 Hz
Material
Plastic, Metal
Mounting
Plug-in socket Mount
Mounting Type
Plug-in socket
Number Of Poles
Plug-in socket
Operating Temperature
-20 to 60 F
Operating Temperature, Maximum
60 F
Operating Temperature, Minimum
-20 F
Poles
DPDT
Series
TDR
Size
81.3mm (H) x 60.7mm (W) x 45.2mm (D)
Special Features
10Y WARR
Standard
CE/UR/CSA
Sub Brand
SSAC
Voltage Rating
120 VAC
The TDR Series of time-delay relays are comprised of digital circuitry and an isolated, 10A relay output. The ON and OFF delays are selected by means of two, ten position binary switches, which allow the setting of the desired delay to be precise every time. Operation (Recycling - ON Time First): Upon application of input voltage, the green LED glows, the output relay is energized, the red LED glows, and the T1 ON time begins. At the end of the ON time, the output de-energizes, the red LED turns OFF and the T2, OFF time begins. At the end of the OFF time, the output relay energizes and the cycle repeats as long as input voltage is applied. Reset: Removing input voltage resets the output and time delays, and returns the sequence to the first delay. Operation (Recycling - OFF Time First): Upon application of input voltage, the green LED glows, the T1 OFF time begins, the load is OFF. At the end of the OFF time, the T2 ON time begins, the load energizes, and the red LED glows. At the end of the ON time the load de-energizes and the red LED turns OFF. The cycle repeats until input voltage is removed. Reset: Removing input voltage resets the output and the sequence to the OFF time.

TDR4A12

The TDR Series of time-delay relays are comprised of digital circuitry and an isolated, 10A relay output. The ON and OFF delays are selected by means of two, ten position binary switches, which allow the setting of the desired delay to be precise every time. Operation (Recycling - ON Time First): Upon application of input voltage, the green LED glows, the output relay is energized, the red LED glows, and the T1 ON time begins. At the end of the ON time, the output de-energizes, the red LED turns OFF and the T2, OFF time begins. At the end of the OFF time, the output relay energizes and the cycle repeats as long as input voltage is applied. Reset: Removing input voltage resets the output and time delays, and returns the sequence to the first delay. Operation (Recycling - OFF Time First): Upon application of input voltage, the green LED glows, the T1 OFF time begins, the load is OFF. At the end of the OFF time, the T2 ON time begins, the load energizes, and the red LED glows. At the end of the ON time the load de-energizes and the red LED turns OFF. The cycle repeats until input voltage is removed. Reset: Removing input voltage resets the output and the sequence to the OFF time.
The TDR Series of time-delay relays are comprised of digital circuitry and an isolated, 10A relay output. The ON and OFF delays are selected by means of two, ten position binary switches, which allow the setting of the desired delay to be precise every time. Operation (Recycling - ON Time First): Upon application of input voltage, the green LED glows, the output relay is energized, the red LED glows, and the T1 ON time begins. At the end of the ON time, the output de-energizes, the red LED turns OFF and the T2, OFF time begins. At the end of the OFF time, the output relay energizes and the cycle repeats as long as input voltage is applied. Reset: Removing input voltage resets the output and time delays, and returns the sequence to the first delay. Operation (Recycling - OFF Time First): Upon application of input voltage, the green LED glows, the T1 OFF time begins, the load is OFF. At the end of the OFF time, the T2 ON time begins, the load energizes, and the red LED glows. At the end of the ON time the load de-energizes and the red LED turns OFF. The cycle repeats until input voltage is removed. Reset: Removing input voltage resets the output and the sequence to the OFF time.

TDR4A22

The TDR Series of time-delay relays are comprised of digital circuitry and an isolated, 10A relay output. The ON and OFF delays are selected by means of two, ten position binary switches, which allow the setting of the desired delay to be precise every time. Operation (Recycling - ON Time First): Upon application of input voltage, the green LED glows, the output relay is energized, the red LED glows, and the T1 ON time begins. At the end of the ON time, the output de-energizes, the red LED turns OFF and the T2, OFF time begins. At the end of the OFF time, the output relay energizes and the cycle repeats as long as input voltage is applied. Reset: Removing input voltage resets the output and time delays, and returns the sequence to the first delay. Operation (Recycling - OFF Time First): Upon application of input voltage, the green LED glows, the T1 OFF time begins, the load is OFF. At the end of the OFF time, the T2 ON time begins, the load energizes, and the red LED glows. At the end of the ON time the load de-energizes and the red LED turns OFF. The cycle repeats until input voltage is removed. Reset: Removing input voltage resets the output and the sequence to the OFF time.
The TRDU Series is a versatile universal time delay relay with 21 selectable single and dual functions. The dual functions replace up to three timers required to accomplish the same function. Both the function and the timing range are selectable with switches located on the face of the unit. Two LED's indicate input voltage and output status. This device offers full 10A isolated relay output contacts in either SPDT or DPDT. The TRDU replaces hundreds of part numbers, thereby, reducing your stock inventory requirements. 21 Functions: Five switches are provided to set one of 10 single or 11 dual modes of operation. See datasheet for a complete list of singe and dual functions.

TRDU120A3

The TRDU Series is a versatile universal time delay relay with 21 selectable single and dual functions. The dual functions replace up to three timers required to accomplish the same function. Both the function and the timing range are selectable with switches located on the face of the unit. Two LED's indicate input voltage and output status. This device offers full 10A isolated relay output contacts in either SPDT or DPDT. The TRDU replaces hundreds of part numbers, thereby, reducing your stock inventory requirements. 21 Functions: Five switches are provided to set one of 10 single or 11 dual modes of operation. See datasheet for a complete list of singe and dual functions.
The TRDU Series is a versatile universal time delay relay with 21 selectable single and dual functions. The dual functions replace up to three timers required to accomplish the same function. Both the function and the timing range are selectable with switches located on the face of the unit. Two LED's indicate input voltage and output status. This device offers full 10A isolated relay output contacts in either SPDT or DPDT. The TRDU replaces hundreds of part numbers, thereby, reducing your stock inventory requirements. 21 Functions: Five switches are provided to set one of 10 single or 11 dual modes of operation. See datasheet for a complete list of singe and dual functions.

TRDU24A3

The TRDU Series is a versatile universal time delay relay with 21 selectable single and dual functions. The dual functions replace up to three timers required to accomplish the same function. Both the function and the timing range are selectable with switches located on the face of the unit. Two LED's indicate input voltage and output status. This device offers full 10A isolated relay output contacts in either SPDT or DPDT. The TRDU replaces hundreds of part numbers, thereby, reducing your stock inventory requirements. 21 Functions: Five switches are provided to set one of 10 single or 11 dual modes of operation. See datasheet for a complete list of singe and dual functions.
The KRDM Series is a compact time delay relay measuring only 2 in. (50.8 mm) square. Its solid-state timing circuit provides excellent repeat accuracy and stability. Encapsulation protects against shock, vibration, and humidity. The KRDM Series is a cost effective approach for OEM applications that require small size, isolation, reliability, and long life. Operation (Delay-on-Make): Upon application of input voltage, the time delay begins. The output is de-energized before and during the time delay. At the end of the time delay, the output relay energizes and remains energized until input voltage is removed. Reset: Removing input voltage resets the time delay and output.

KRDM421

The KRDM Series is a compact time delay relay measuring only 2 in. (50.8 mm) square. Its solid-state timing circuit provides excellent repeat accuracy and stability. Encapsulation protects against shock, vibration, and humidity. The KRDM Series is a cost effective approach for OEM applications that require small size, isolation, reliability, and long life. Operation (Delay-on-Make): Upon application of input voltage, the time delay begins. The output is de-energized before and during the time delay. At the end of the time delay, the output relay energizes and remains energized until input voltage is removed. Reset: Removing input voltage resets the time delay and output.

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.