KRPSD21B - KRPS DOB Timers Series

Series: KRPS DOB Timers
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Littelfuse Delay on Break Timers
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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 KRPS Series is a factory programmed time delay relay available with 1 of 15 functions and measures only 2 inches square. The KRPS offers a wide range of fixed, onboard, or externally adjustable time delays. The output relay contacts offer a full 10A rating with complete isolation. Its microcontroller timing circuit provides excellent repeat accuracy and stability. Encapsulation protects against shock, vibration, and humidity. The KRPS Series is a cost effective approach for OEM applications that require small size, isolation, accuracy, and long life. Special time ranges and functions are available.


Operation (Delay on Break)
Input voltage must be applied before and during timing. Upon closure of the initiate switch, the output relay energizes. The time delay begins when the initiate switch is opened. The output remains energized during timing. At the end of the time delay, the output de-energizes. The output will energize if the initiate switch is closed when input voltage is applied.
Reset: Re-closing the initiate switch during timing resets the time delay. Removing input voltage resets the time delay and output.

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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) 12 or 48 V dc
Input Tolerance (%) -15% - 20%
Input DC Ripple (%) ≤10%
Output Type Isolated relay contacts
Output Form SPDT
Output Load Rating (VA) 10 A resistive @ 125 V ac; 5 A resistive @ 230 V ac and 28 V dc; 1/4 hp @ 125 V ac
Time Delay Type Microcontroller
Time Delay Range 0.1 - 10 s onboard adjustable
Time Delay Tolerance (%) ±2%
Reset Time (ms) ≤150
Initiate Time (ms) ≤40; 750 operations per minute
Repeat Accuracy (%) ±0.5% or 20 ms whichever is greater
Setpoint vs Ambient Temperature and Operating Voltage (%) ≤±2%
Switching Voltage Maximum (V) 250
Insulation Resistance ≥100
Circuitry Encapsulated
Polarity DC units are reverse polarity protected
Life Electrical: 1 x 10⁵; Mechanical: 1 x 10⁷
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 2 H x 2 W in. (50.8 x 50.8 mm)
Weight (lbs/g) 0 Kg
Dimensions 2 H x 2 W in. (50.8 x 50.8 mm)

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