THD7421A - Interval Timers Series

Series: THD Interval Timers
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The THD2 Series combines accurate timing circuitry with high power solid-state switching. It can switch motors, lamps, and heaters directly without a contactor. You can reduce labor, component cost, and increase reliability with these small, easy-to-use THD2 Series timers.


Operation (Interval)
Upon application of input voltage, the time delay begins. The output energizes during the time delay. At the end of the time delay, the output de-energizes and remains de-energized until input voltage is removed.
Reset: Removing input voltage resets the time delay and the 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) 120 V ac
Input Tolerance (%) ±20%
Input AC Line Frequency (Hz) 50/60
Output Type Solid state
Output Form NO - closed during timing
Output Load Rating (VA) 6 A steady state; 60 A inrush
Minimum Output Load Current (A) 100
Output Voltage Drop (V) Effective drop: ≤3 V
Time Delay Type Digital
Time Delay Range 1 - 100 s externally adjustable
Time Delay Tolerance (%) ≤±10%
Recycle Time (ms) After timing: ≤150; During timing: ≤350
Repeat Accuracy (%) ±0.5% or 20 ms whichever is greater
Setpoint vs Ambient Temperature and Operating Voltage (%) ≤±2%
Insulation Resistance ≥100
Dielectric Breakdown ≥2000V terminals to mounting surface
Circuitry Encapsulated
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.