Series 1640 Floating Contact Null Switch 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 Instruments, LLC innovation. The
Dwyer® Model 1640 Differential Pressure Switch resembles the high precision large diaphragm Series 1630 switches. However, the Model 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.
Product Applications
- Damper positioning
- Duct air control
Specifications
- Service:
- Air and non-combustible, compatible gases.
- Wetted Materials:
- Consult factory.
- Temperature Limits:
- -30 to 110°F (-34.4 to 43.3°C).
- Pressure Limits:
- 10 psig (68.95 kPa) continuous, 25 psig (172.4 kPa) surge.
- Switch Type:
- SPDT floating contact (not snap action).
- Electrical Rating:
- Non-inductive: 2.5 A @ 110 VAC, 1.5 A @ 220 VAC, 1 A @ 24 VDC, 0.5 A @ 110 VAC; Inductive: 1 A @ 110 VAC, 0.5 A @ 220 VAC, 0.5 A @ 24 VDC. (De-rate 70-80% for very slow pressure changes.)
- Electrical Connections:
- 3 screw type.
- Process Connections:
- 1/8" female NPT.
- Mounting Orientation:
- Diaphragm in vertical position. Consult factory for other position orientations.
- Set Point Adjustment:
- Screw type.
- Weight:
- 4 lb 13 oz (2.18 kg).
- Compliance:
- CE.
Features
- 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
Options
- -WP Weatherproof Housing.
Approvals
Model Chart
| EXAMPLE | 1640 | 0 | AT | Series 1640-0-AT Floating Contact Null Switch for High and Low Actuation, range 0.01-0.2" w.c., with aluminum tag. |
| SERIES | 1640 | Floating Contact Null Switch for High and Low Actuation | ||
| RANGE | 0 1 2 5 10 .25KPA 1KPA 1.5KPA 3KPA |
0.01 - 0.2" w.c. 0.20-1.0" w.c. 1.0-4.0" w.c. 2.0-6.0" w.c. 3.0-12.0" w.c. 0.05-0.25 kPa 0.4-1.0 kPa 0.5-1.5 kPa 1.0-3.0 kPa |
||
| OPTIONS | AT LC PRESET ST |
Aluminum Tag Less Conduit Preset Stainless Steel Tag |
| Model | Description | Availability* | Price |
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