ASTUD3 - Multifunction Time Delay Relay Series

Series: ASQU ASTU
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The ASQU and ASTU Series of 17.5 mm, knob adjustable, universal solid-state timers offer multiple functions, voltages, and time delay ranges. Choose one of 5 functions and 4 time delay ranges via 4 selection switches located on face of the unit. Adjustment through the time range is accomplished by an onboard knob.


The ASQU Series has quick connect terminal and the ASTU Series has terminal blocks.

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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) 9 or 110 V dc; 9.4 or 110 V dc; 120 or 230 V ac
Input Tolerance (%) 9 - 110 V dc: -0% - 20% @-25°C; 9.4 - 110 Vdc: -0% - 20% @ -40°C; 24 - 240 Vac: -20% - 10%
Input DC Ripple (%) ≤10%
Output Type Solid state
Output Form NO
Output Load Rating (VA) 0.7 A steady state; 10 A inrush
Output Voltage Drop (V) ≅1.5 V @ 0.7 A
Time Delay Type Microcontroller based with ceramic resonator and watchdog circuitry
Time Delay Range 0.1 - 10 s; 1 - 100 s; 10 - 1000 s; 1 - 100 m
Time Delay Tolerance (%) ±2% or ±50 ms whichever is greater
Reset Time (ms) ≤300
Initiate Time (ms) Single shot and delay-on-break: ≤32
Adjustment Type Knob with dial; 2 switches select 1 of 4 multipliers
Repeat Accuracy (%) ±1% or 50 ms whichever is greater
Setpoint vs Ambient Temperature and Operating Voltage (%) ≤±2% or 50 ms whichever is greater
Surge Protection IEEE C62.41-1991 Level A
Dielectric Breakdown ≥2000V terminals to mounting surface
Circuitry Encapsulated
Polarity DC units are reverse polarity protected
Termination Type 0.197 in (5 mm) push-on terminal blocks for up to #14 AWG (2.5 mm²) wire
Mounting Method DIN rail: Snap on to 32 mm DIN 1 and 35 mm DIN 3 rail; Surface mount: 2 #6 (M3.5 x 0.6) screws or quick mount fasteners
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
Weight (lbs/g) 0 Kg
To request product environmental information, please complete the Product Environmental Information Request Form.