THD7 Series - Time Delay Relay

Series: THD7
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The THD7 Series utilizes only two terminals connected in series with the load. Interval timing mode is achieved by using a small portion of the AC sine wave allowing sufficient voltage for circuit operation. The THD7 Series can be used for interval or delay-on break timing. It is designed to operate large loads directly, such as motors, heater elements, and motor starters.

Operation (Interval)

Upon application of input voltage, the output energizes and the time delay begins. The output remains energized throughout the time delay. At the end of the time delay the output de-energizes and remains de-energized until power is removed. Reset: Removing input voltage resets the time delay and the output.

Operation (Delay-on-Break)

Upon closure of SW1, the load energizes and the timer is reset (zero voltage across its input terminals). Opening SW1 re-applies input voltage to the timer, the load remains energized and the time delay begins. At the end of the time delay the output de-energizes. If SW1 is open when power is applied, the load will energize for the time delay then de-energize. Reset: Re-closing SW1 resets the timer.

Product Literature

Access specifications, certifications, check availability and order parts below

Catalog #Input
Voltage (V)		Output
Form		Time Delay RangeTermination TypeMounting MethodDimensionsWeight (lbs/g)CircuitryDielectric BreakdownHumidityInput AC Line Frequency (Hz)Input Tolerance (%)Insulation ResistanceMinimum Output Load Current (A)Output Load Rating (VA)StockSamplesCompare
THD7421A120 V acNO - closed during timing1 - 100 s externally adjustable0.25 in. (6.35 mm) male quick connect terminalsSurface mount with 1 #10 (M5 x 0.8) screw2 H x 2 W in. (50.8 x 50.8 mm)0 KgEncapsulated≥2000V terminals to mounting surface95% relative : non-condensing50/60±20%≥1001006 A steady state; 60 A inrushCheckOrder
THD7621C230 V acNO - closed during timing1 - 100 s externally adjustable0.25 in. (6.35 mm) male quick connect terminalsSurface mount with 1 #10 (M5 x 0.8) screw2 H x 2 W in. (50.8 x 50.8 mm)0 KgEncapsulated≥2000V terminals to mounting surface95% relative : non-condensing50/60±20%≥10010020 A steady state; 200 A inrushCheckOrder
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