Dwyer Series 1640 Floating Contact Null Switch 1640-0

Dwyer Series 1640 Floating Contact Null Switch 1640-0,
for High and Low Actuation,
The unique electric switch design in the Series 1640 Floating Contact Null Switch
for High and Low Actuation is another Dwyer Instrument, Inc. innovation.
The Dwyer® Model 1640 Differential Pressure Switch resembles the high precision large
diaphragm Series 1630 switches. However, the Model 1640 is equippe 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 close when rising pressure differential reaches
the preset level. The “low” circuit will close when falling pressure differential
reaches the preset level.