NEW Dwyer Instruments Differential Pressure Null Switch 1640-5 – Water H2O 2-6″
The Dwyer Model 1640 Differential Pressure Switch resembles the Series 1630 switches. Drawing shows the switching action schematically. The “high” circuit will be closed when rising pressure differential reaches the preset level.
Dwyer Instruments Differential Pressure Null Switch 1640-5
ONE (1) Null Switch. This switch appears unused in its original box. The unit is marked “Dwyer Null Switch No. 1640-5”. set and. 18 max. Color in photos may not exactly match physical item due to image rendering differences.