The D21-P electronic controller has been designed to take full advantage of our patented Air-Flow Sensor which modulates the heater’s capacity according to the quantity of air flowing through the heater by responding to the radiant heat of the elements even at very low CFMs. With normal airflow the controller will operate at full power. When the airflow drops below the minimum airflow, the controller will still operate but at reduced power. It will also safely shut down the heater in case of a total loss of airflow. The D21-P has a single output and the D22-P is equipped with two outputs effectively doubling the capacity. In cases with even larger loads, a D21-PS may be used instead to drive up to 4 SSRs. The ‘P’ versions of controllers such as D21-P operate with an input signal of 0 - 10 VDC or AC/DC pulse. It is also possible to adapt the wiring to use a simple ON/OFF contact to turn the controller full on and off. To switch the input between 0-10 VDC and AC/DC pulse, simply remove and replace the jumper according to the label.
Mercury contactors are used for stage switching. Advantages: silent operation. Exceptionally reliable. Long life expectancy (Tested for 1,000,000 cycles) Note: Mercury contactors are position sensitive, hence it is important to specify in which position the heater is to be instal...Learn More
Pilot lights are mounted on the control box to indicate that either a function of the heater is operating or a failure condition is present. The most commonly specified pilot lights functions are: power on, heating on, no airflow, overheating, stages on. The pilot lights' functio...Learn More
The D21-PSSR electronic controller has been designed to be a compact solution to take full advantage of our patented Air-Flow Sensor which modulates the heater’s capacity according to the quantity of air flowing through the heater by responding to the radiant heat of the elements...Learn More
2060 Lucien Thimens
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