1640 Floating Contact Null Switch for High and Low Actuation
Visual set point adjustment, adjustable null zone, and functions as a null switch
The unique electric switch design in the Series 1640 is another Dwyer Instrument, Inc. innovation. The Dwyer® Series 1640 Differential Pressure Switch resembles the Series 1630 switches. However, the Series 1640 is equipped with a single pole, double throw floating contact switch (not snap acting) so it functions as a null switch.
As the diaphragm moves in response to pressure changes, it moves the floating contact to cause switching action at two preset points with no switching action between these points. The "high" circuit will be closed when rising pressure differential reaches the preset level. The "low" circuit will be closed when falling pressure differential reaches the preset level.
Caution: For use only with air or compatible gases
• Floating “null” switch supports applications requiring two set point actions such as open and close damper control
• Visible set point indicator simplifies operation and trouble shooting
• Large diaphragm provides low range accuracy providing precise control
• Damper positioning
• Duct air control
