CT HVAC Timer Series - Delay on Make/Delay on Break Timer

Littelfuse HVAC Relays
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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.

Access specifications, certifications, check availability and order parts below

Catalog #Input
Voltage (V)
Storage Temperature (F/C)Time Delay RangeSample CapableCompare
CT1S3024 VACNO-40° to 85°C (-40°F to 185°F)DOM: 1s; DOB: 30sNo
CT1S4524 VACNO-40° to 85°C (-40°F to 185°F)DOM: 1s; DOB: 45sNo
CT1S824 VACNO-40° to 85°C (-40°F to 185°F)DOM: 1s; DOB: 8sNo
CT1S9024 VACNO-40° to 85°C (-40°F to 185°F)DOM: 1s; DOB: 90sNo
CT30S124 VACNO-40° to 85°C (-40°F to 185°F)DOM: 30s; DOB: 1sNo
CT45S4524 VACNO-40° to 85°C (-40°F to 185°F)DOM: 45s; DOB: 45sNo
CT5S30024 VACNO-40° to 85°C (-40°F to 185°F)DOM: 5s; DOB: 300sNo
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pdf icon CT Series Datasheet - HVAC

pdf icon Building and Home Automation Application Guide

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