Single Shot Timer Series - Single Shot Timer

Series: Single Shot Timer
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The KRDS Series is a compact time delay relay measuring only 2 in. (50.8 mm) square. Its microcontroller timing circuit provides excellent repeat accuracy and stability. Encapsulation protects against shock, vibration, and humidity. The KRDS Series is a cost effective approach for OEM applications that require small size, isolation, reliability, and long life.


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
KRDS12012 V dcSPDT-40° to 85°C (-40° to 185°F)0.1 - 10 s onboard adjustable2 H x 2 W in. (50.8 x 50.8 mm)CheckOrder
KRDS22124 V ac/dcSPDT-40° to 85°C (-40° to 185°F)1 - 100 s onboard adjustable2 H x 2 W in. (50.8 x 50.8 mm)CheckOrder
KRDS420120 V acSPDT-40° to 85°C (-40° to 185°F)0.1 - 10 s onboard adjustable2 H x 2 W in. (50.8 x 50.8 mm)CheckOrder
KRDS421120 V acSPDT-40° to 85°C (-40° to 185°F)1 - 100 s onboard adjustable2 H x 2 W in. (50.8 x 50.8 mm)CheckOrder
KRDS424120 V acSPDT-40° to 85°C (-40° to 185°F)1 - 100 m onboard adjustable2 H x 2 W in. (50.8 x 50.8 mm)CheckOrder
KRDS430120VACSPDT-40° to 85°C (-40°F to 185°F)0.1 - 10s externally adjustable2.00 x 2.00 x 1.21 in. (50.8 x 50.8 x 30.7mm)
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