HRDS Series - Single Shot Timer

Series: HRDS
Questions? Contact Littelfuse Support
External overview image
Roll Over to Zoom
Disclaimer Notice

Littelfuse products are not designed for, and shall not be used for, any purpose (including, without limitation, automotive, military, aerospace, medical, life-saving, life-sustaining or nuclear facility applications, devices intended for surgical implant into the body, or any other application in which the failure or lack of desired operation of the product may result in personal injury, death, or property damage) other than those expressly set forth in applicable Littelfuse product documentation. Warranties granted by Littelfuse shall be deemed void for products used for any purpose not expressly set forth in applicable Littelfuse documentation. Littelfuse shall not be liable for any claims or damages arising out of products used in applications not expressly intended by Littelfuse as set forth in applicable Littelfuse documentation. The sale and use of Littelfuse products is subject to Littelfuse Terms and Conditions of Sale, unless otherwise agreed by Littelfuse. "Littelfuse" includes Littelfuse, Inc., and all of its affiliate entities.

The HRDS Series combines an electromechanical relay output with microcontroller timing circuitry. It offers 12 to 230V operation in five options and factory fixed, onboard or external adjustable time delays with a repeat accuracy of ±0.5%. The output contact rating allows for direct operation of heavy loads, such as compressors, pumps, blower motors, heaters, etc. This series is ideal for OEM applications where cost is a factor.


Operation (Single Shot)
Input voltage must be applied before and during timing. Upon momentary or maintained closure of the initiate switch, the output relay energizes for a measured interval of time. At the end of the delay, the output de-energizes. Opening or reclosing the initiate switch during timing has no affect on the time delay. The output will energize if the initiate switch is closed when input voltage is applied.
Reset: Reset occurs when the time delay is complete and the initiate switch is opened. Loss of input voltage resets the time delay and output.

Product Literature

For Technical Questions

Call +1 800-832-3873 or email us at relays@littelfuse.com 

Access specifications, certifications, check availability and order parts below

Catalog #Input
Voltage (V)		Output
Form		Storage Temperature (F/C)Time Delay RangeDimensionsStockSamplesCompare
HRDS12012 V dcNon-isolated SPDT-40° to 85°C (-40° to 185°F)0.1 - 10 s onboard adjustable3 H x 2 W in. (76.7 x 51.3 mm)CheckOrder
HRDS313M24 V dcNon-isolated SPDT-40° to 85°C (-40° to 185°F)3 m fixed3 H x 2 W in. (76.7 x 51.3 mm)CheckOrder
HRDS32124 V dcNon-isolated SPDT-40° to 85°C (-40° to 185°F)1 - 100 s onboard adjustable3 H x 2 W in. (76.7 x 51.3 mm)CheckOrder
HRDS421120 V acNon-isolated SPDT-40° to 85°C (-40° to 185°F)1 - 100 s onboard adjustable3 H x 2 W in. (76.7 x 51.3 mm)CheckOrder
HRDS430120 V acNon-isolated SPDT-40° to 85°C (-40° to 185°F)0.1 - 10 s externally adjustable3 H x 2 W in. (76.7 x 51.3 mm)Check
Part # Part Description RoHS Pb-free RoHS (2015/ 863/EU) Certificate REACH (SVHC’s) Declaration Halogen Free REACH (SVHC’s) IPC-Material Declaration
HRDS321 SINGLE SHOT TIMER RoHS No 04/23/2021 PbFree No 04/23/2021 CoC_RoHS9_HRDS321 Yes
04/23/2021
If the product environmental information that you are looking for does not appear in this tab,
please complete the Product Environmental Information Request Form.