HRDM3112S - HRDM Series

Series: HRDM
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 HRDM Series combines an electromechanical relay output with microcontroller timing circuitry. It offers 12 to 230V operation in five ranges 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 (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.

Check Stock Order Samples

Product Literature

For Technical Questions

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

Property (Mouseover for details) Value
Input Voltage (V) 24 V dc
Input Tolerance (%) -15% - 20%
Output Type Electromechanical relay
Output Form Non-isolated SPDT
Output Load Rating (VA) General Purpose: SPDT-NO: 125/240 V ac ≅30 A; SPDT-NC ≅15 A; Resistive: SPDT-NO ≅30 A for 125/240 V ac and 20 A for 28 V dc; SPDT-NC ≅15 A for 125/240 V ac and 10 A for 28 V dc; Motor Load: SPDT-NO ≅1 hp for 125 V ac and 2 hp for 240 V ac; SPDT-NC ≅1/4 hp for 125 V ac and 1 hp for 240 V ac
Time Delay Type Microcontroller
Time Delay Range 12 s fixed
Time Delay Tolerance (%) ±5%
Reset Time (ms) ≤150
Repeat Accuracy (%) ±0.5% or 20 ms whichever is greater
Setpoint vs Ambient Temperature and Operating Voltage (%) ≤±2%
Surge Protection IEEE C62.41-1991 Level A
Insulation Resistance ≥100
Dielectric Breakdown ≥2000V terminals to mounting surface
Circuitry Encapsulated
Polarity DC units are reverse polarity protected
Life Electrical: 1 x 10⁵ 3 x 104 for 1 hp - 6000 for 1/4 hp 1 hp and 2 hp; Mechanical: 1 x 10⁶
Power Consumption ≤2 W
Termination Type 0.25 in. (6.35 mm) male quick connect terminals
Mounting Method Surface mount with 1 #10 (M5 x 0.8) screw
Operating Temperature -40° to 60°C (-40° to 140°F)
Storage Temperature (F/C) -40° to 85°C (-40° to 185°F)
Humidity 95% relative : non-condensing
Dimensions 3 H x 2 W in. (76.7 x 51.3 mm)
Weight (lbs/g) 0 Kg
Dimensions 3 H x 2 W in. (76.7 x 51.3 mm)

To request product environmental information, please complete the Product Environmental Information Request Form.