Dwyer DH Series Digital Multifunction Differential Pressure Controller
The Series DH Digihelic® Differential Pressure Controller is a 3-in-1 instrument possessing a digital display gage, control relay switches, and a transmitter with current output. The Digihelic® controller is the ideal instrument for pressure, velocity and flow applications, achieving a 0.5% full-scale accuracy on ranges from 0.25 to 100 in w.c. The Digihelic® controller allows the selection of pressure, velocity or volumetric flow operation in several commonly used engineering units. Two SPDT control relays with adjustable dead bands are provided along with a scalable 4-20 mA process output. The Series DH provides extreme flexibility in power usage by allowing 120/220 VAC and also 24 VDC power which is often used in control panels.
Programming is easy using the menu key to access 5 simplified menus which provide access to: security level; selection of pressure, velocity or flow operation; selection of engineering units; K-factor for use with flow sensors; rectangular or circular duct for inputting area in flow applications; set point control or set point and alarm operation; alarm operation as a high, low or high/low alarm; automatic or manual alarm reset; alarm delay; view peak and valley process readings; digital damping for smoothing erratic process applications; scaling the 4-20 mA process output to fit your application’s range; Modbus® communications; and field calibration.
BENEFITS/FEATURES
• 3-in-1 instrument allows the reduction of several instruments with one product, saving inventory, installation time and money
• Velocity of flow modes, a square root output coincides with the actual flow curve for greater precision
• Power usage of 120/220 VAC or 24 VDC provides flexibility to incorporate device in control panel • Secure menu program provides access to device operation only for the right skill level
• Modbus® communications supports Process and HVAC system integration and control APPLICATIONS
• SCFM duct flow • Industrial ovens air flow • Filter status • Clean room pressurization • Fume hood air flow
• Surgical and medical room pressurization
• Damper and fan control 1-3/4
SPECIFICATIONS Service: Air and non-combustible, compatible gases.
Wetted Materials: Consult factory.
Housing Material: ABS plastic,
UL approved 94 V-0.
Accuracy: ±0.5% at 77°F (25°C) including hysteresis and repeatability.
Stability: < ±1% per year.
Pressure Limits: Ranges ≤ 2.5 in w.c. = 2 psi; 5˝: 5 psi; 10˝: 5 psi; 25˝: 5 psi; 50˝: 5 psi, 100˝: 9 psi. Temperature Limits: 32 to 140°F (0 to 60°C).
Compensated Temperature Limits: 32 to 140°F (0 to 60°C).
Thermal Effects: 0.020%/°F (0.036/°C) from 77°F (25°C).
Power Requirements: High voltage power = 100-240 VAC, 50-400 Hz or 132-240 VDC.
Low voltage power = 24 VDC ±20%.
Power Consumption: Low voltage power = 24 VDC - 130 mA max; High voltage power = 100-240 VAC, 132-240 VDC - 7VA max.
Output Signal: 4-20 mA DC into 900 Ω max.
Zero and Span Adjustments: Accessible via menus.
Response Time: 250 ms.
Display: 4 digit LCD 0.4˝ height. LED indicators for set point and alarm status.
Electrical Connections: Screw terminals.
Process Connections: Compression fitting for use with 1/8˝ ID X 1/4˝ OD tubing (3.175 mm ID x 6.35 mm OD). Optional barbed fitting for 3/16˝ ID tubing.
Enclosure Rating: Face designed to meet NEMA 4X (IP66).
Mounting Orientation: Mount unit in horizontal plane.
Size: 1/8 DIN.
Panel Cutout: 1.772 x 3.620 in (45 x 92 mm).
Weight: 14.4 oz (408 g).
Serial Communications: Modbus® RTU, RS485, 9600 baud.
Compliance: CE, UL.
SWITCH SPECIFICATIONS
Switch Type: 2 SPDT relays.
Electrical Rating: 8 amps at 240 VAC resistive.
Set Point Adjustment: Adjustable via keypad on face.
Part #:
DH007: Measurement Pressure, Max 10 inH₂O
DH008: Measurement Pressure, Max 25 inH₂O
DH009: Measurement Pressure, Max 50 inH₂O
PDFs & Manuals
Series DH Digihelic® Catalog Page DH - Digihelic® Modbus® Register List DH - DH Quick Set-up Sheet
