CT1S45 - CT HVAC Timers Series

Series: CT HVAC Timers
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The CT Series combines a delay-on-make and delay-on-break time delay into one unit and may be used to control fan delays in heating and/or cooling equipment. The CT includes bypass circuitry to allow it to operate with cooling anticipators ? 3000 ohms. It is designed to operate in 24VAC control circuits. Several CT modules may be combined to provide sequencing on of any number of loads and sequencing off of the same loads, such as electric heating elements.


Operation (Delay-on-Make/Delay-on-Break)
Forced Air Heating or Air Conditioning (as shown): When the thermostat closes, the compressor relay is immediately energized. At the end of a fixed delay-on-make delay (T1), the fan relay is energized. When the thermostat opens, the compressor relay is de-energized and the delay-on-break delay is initiated. On completion of the fixed delay-on- break delay (T2) the fan relay is de-energized. If the thermostat is reclosed during the delay-on-break delay, the delay-on-break delay is reset and the fan relay remains energized. If the thermostat is closed when input voltage is applied, the delay-on-make delay (T1) begins as normal.
Reset: Removing input voltage resets the output and time delays.

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Call +1 800-832-3873 or email us at relays@littelfuse.com 

Property (Mouseover for details) Value
Input Voltage (V) 24 V ac
Input Tolerance (%) ±15%
Input AC Line Frequency (Hz) 50/60
Output Type Solid state
Output Form NO
Output Load Rating (VA) 0.75 A steady state; 5 A inrush @ 55°C
Output Voltage Drop (V) ≅1.25 V
Time Delay Type Microcontroller
Time Delay Range DOM: 1 s; DOB: 45 s
Time Delay Tolerance (%) ≤±20%
Recycle Time (ms) ≤300
Repeat Accuracy (%) ±5%
Thermostat Anticipator Resistor (Ohms) Anticipator resistor: ≥3000
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 70°C (-40° to 158°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)

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