KRDR Series - Recycling Timer

Littelfuse Recycle Time Delay Relays
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The KRDR 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 KRDR Series is a cost effective recycling timer for OEM applications that require small size, isolation, reliability, and long life.


Operation (Recycling - ON Time First)

Upon application of input voltage, the output relay energizes and the T2 ON time begins. At the end of the ON time, the output de-energizes and the T1 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 the time delays, and returns the sequence to the ON time.


Operation (Recycling - OFF Time First)

Upon application of input voltage, the T1 OFF time begins. At the end of the OFF time, the T2 ON time begins and the load energizes. At the end of the ON time the load de-energizes, and the cycle repeats until input voltage is removed.
Reset: Removing input voltage resets the output and the sequence to the OFF time.

Access specifications, certifications, check availability and order parts below

Catalog #Input
Voltage (V)
Output
Form
Max. Output
Voltage (V)
Storage Temperature (F/C)Time Delay RangeSample capableCompare
KRDR115MB25M12VDCSPDT250VAC-40° to 85°C (-40°F to 185°F)ON: 5m fixed; OFF time first: 25m fixedNo
KRDR120A012VDCSPDT250VAC-40° to 85°C (-40°F to 185°F)ON time first: 0.1 - 10s adjustable; OFF: 0.1 - 10s adjustableNo
KRDR121A112VDCSPDT250VAC-40° to 85°C (-40°F to 185°F)ON time first: 1 - 100s adjustable; OFF: 1 - 100s adjustableNo
KRDR320B024VDCSPDT250VAC-40° to 85°C (-40°F to 185°F)ON: 0.1 - 10s adjustable; OFF time first: 0.1 - 10s adjustableNo
KRDR321A424VDCSPDT250VAC-40° to 85°C (-40°F to 185°F)ON time first: 1 - 100s adjustable; OFF: 1 - 100m adjustableNo
KRDR321B424VDCSPDT250VAC-40° to 85°C (-40°F to 185°F)ON: 1 - 100s adjustable; OFF time first: 1 - 100m adjustableNo
KRDR420A3120VACSPDT250VAC-40° to 85°C (-40°F to 185°F)ON time first: 0.1 - 10s adjustable; OFF: 0.1 - 10m adjustableNo
KRDR421A4120VACSPDT250VAC-40° to 85°C (-40°F to 185°F)ON time first: 1 - 100s adjustable; OFF: 1 - 100m adjustableNo
KRDR424A0120VACSPDT250VAC-40° to 85°C (-40°F to 185°F)ON time first: 1 - 100m adjustable; OFF: 0.1 - 10s adjustableNo
KRDR424A4120VACSPDT250VAC-40° to 85°C (-40°F to 185°F)ON time first: 1 - 100m adjustable; OFF: 1 - 100m adjustableNo
KRDR440.5SA0120VACSPDT250VAC-40° to 85°C (-40°F to 185°F)ON time first: 0.5s fixed; OFF: 0.1 - 10s adjustableNo