Floating Contact Null Switch

1640 - Dwyer Instruments Inc. (Dwyer Instruments Inc.)

The unique electric switch design in the 1640 is another Dwyer Instrument, Inc. innovation. The Dwyer Model 1640 Differential Pressure Switch resembles the Series 1630 switches. The Model 1640, however, is equipped with a single pole, double throw floating contact switch (not snap acting) so it functions as a null switch.