DWYER 631B Series Gas/Liquid Low Differential Pressure Transmitter
Gas/liquid low differential pressure transmitter, 500 psig static pressure rating, 4-20mA two-wire output.
- Original Factory Genuine, Tenfold Compensation for Counterfeits
- Full Machine Warranty, Lifetime Maintenance
- In Stock, Shipped on the Same Day
The 631B Series capsule-type differential pressure transmitter can be used with both gases and liquids, has a 500 psig static pressure rating, and provides a standard 4-20mA two-wire output. Wetted materials are brass, silicon and 300 stainless steel, with a NEMA 4X (IP66) enclosure, suitable for differential pressure monitoring of heat exchangers, filters and pump/valve assemblies.
| Parameter Name | Technical Specifications |
|---|---|
| Main specifications | |
| Medium | Compatible with gas or liquid. |
| Wetted materials | Brass, silicon, 300 SS. |
| Accuracy | Transmitter: ±2% F.S. (including linearity, hysteresis and repeatability). Gauge: ±3% of full scale at 70°F (21.1°C). |
| Stability | ±1% F.S./yr. |
| Temperature limit | 20~120°F. (-6.67~48.9°C). |
| Pressure limits | -20" Hg~500 psig (0.677~34.4 bar). |
| Thermal effect | 0.025%/°F (0.045%/°C) including zero and full scale |
| Power Supply | 10-35 VDC. |
| Output | 4~20 mA. |
| Loop impedance | 0-1250 ohms maximum |
| Electrical connection | M-12 circular 4 pin connector. |
| Connection | 1/4" female NPT high and low pressure taps, duplicated - one pair top for air and gas, and one pair bottom for liquids. |
| Enclosure | Designed to meet NEMA 4X (IP66). |
| Mounting orientation | Vertical. Consult factory for other orientations |
| Weight | 8 lb 4 oz (3.74 kg). |
| Certification | CE. |
| Model selection | |
| Selection table | Published on the official website as a screenshot of the selection table; for complete model numbers and ranges, see the official manual "631B.i.pdf" in the documentation package. |
- For gas and liquid, wetted materials are brass, silicon, 300 stainless steel
- Static pressure resistance -20" Hg~500 psig (34.4 bar)
- 4-20mA two-wire, 10-35 VDC supply
- NEMA 4X (IP66) enclosure, front-panel digital pushbuttons for zero and span adjustment
Liquid line differential pressure monitoring
Pressure taps on both sides of heat exchangers and filters, output 4-20mA to the control system.
Pump and valve group differential pressure monitoring
Monitor pump inlet and outlet differential pressure to determine operating conditions and filter blockage.
Need selection advice or bulk quotation?
Send us the working condition parameters (signal type, medium, range, pressure, temperature, connection method), and our engineers will provide a selection scheme and quotation within 1 working day.
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