Series DH Digihelic Differential Pressure Controller
Brand: Dwyer Instruments, LLCThe Series DH Digihelic® Differential Pressure Controller is a 3-in-1 instrument possessing a digital display gauge, 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 inches WC. 
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.
 
With all this packed into one product it is easy to see why the Digihelic® controller is the only instrument you will need for all your pressure applications.
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
 
Specifications
Brand
Accuracy
- ± 0.5 % at 25° C (77° F) Including Hysteresis & Repeatability
 
Adjustment Type
- Adjustable Via Keypad on Face
 
Approvals & Certifications
- CE
 - UL
 
Compensated Temperature
- 0° to 60° C (32° to 140° F)
 
Consumption
- 132-240 Vdc, 7 VA, Max.
 - High Voltage Power: 100-240 Vac
 - Low Voltage Power: 24 Vdc - 130 mA - Max.
 
Display
- 4-digit LCD 0.4" Height LED Indicators for Set Point & Alarm Status
 
Electrical Connectors
- Screw Terminals
 
Electrical Rating
- 8 A at 240 Vac Resistive
 
Enclosure, Body Material
- ABS Plastic, UL Approved 94 V-0
 
Environmental Protection
- IP66
 - NEMA 4X
 
Media
- Air & Non-Combustible, Compatible Gases
 
Mounting
- 1/8" DIN
 
Output
- 4-20 mA DC Into 900 ohms, Max.
 
Power Requirement
- 50-400 Hz or 132-240 Vdc
 - High Voltage Power: 100-240 Vac
 - Low Voltage Power: 24 Vdc ± 20 %
 
Response Time
- 250 ms
 
Sensor Orientation
- Mount Unit in Horizontal Plane
 
Set Point - Decreasing
- Centimeters WC: 0.635 to 254
 - Feet WC: 0.417 to 8.33
 - hPa: 0.623 to 249.1
 - inHg: 0.368 to 7.356
 - inH₂O: 0.25 to 100
 - kPa: 0.249 to 24.91
 - mbar: 0.623 to 249.1
 - mmHg: 0.467 to 186.8
 - mmH₂O: 6.35 to 2,540
 - oz./in²: 0.144 to 57.80
 - Pa: 62.28 to 6,227
 - psi: 0.181 to 3.613
 
Set Point - Increasing
- Centimeters WC: 0.635 to 254
 - Feet WC: 0.417 to 8.33
 - hPa: 0.623 to 249.1
 - inHg: 0.368 to 7.356
 - inH₂O: 0.25 to 100
 - kPa: 0.249 to 24.91
 - mbar: 0.623 to 249.1
 - mmHg: 0.467 to 186.8
 - mmH₂O: 6.35 to 2,540
 - oz./in²: 0.144 to 57.80
 - Pa: 62.28 to 6,227
 - psi: 0.181 to 3.613
 
Span & Zero Adjustments
- Accessible Via Menus
 
Stability
- < ± 1 % Per Year
 
Switch Type
- 2 SPDT Relays
 
Temperature Range
- 0° to 60° C (32° to 140° F)
 
Thermal Drift
- 0.036/°C (0.020 %/°F) from 25° C (77° F)
 
Tube Connection
- 1/8" I.D. x 1/4" O.D. Tubing (3.175 mm I.D. x 6.35 mm O.D.)
 
- 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