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. Combining these 3 features allows the reduction of several instruments with one
product, saving inventory, installation time and money. 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. Bi-directional ranges are also available, but without velocity and volumetric flow.
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. In velocity of flow modes, a
square root output is provided on the 4-20 mA signal to coincide with the actual flow curve. 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.
DH Digital Differental Pressure Controller Specifications
Service: Air and non-combustible, non-conducting 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" 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 to 240 VAC, 50 to 400 Hz or
132 to 240 VDC. Low Voltage Power = 24 VAC ±20%.
Power Consumption: Low Voltage Power = 24 VDC - 130 mA max.
High Voltage Power = 100 to 240 VAC, 132 to 240 VDC - 7VA max.
Output Signal: 4-20 mA DC into 900 ohms max.
Zero & 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 3/16" OD x 1/8" 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" (45 x 92 mm).
Weight: 14.4 oz (408 g).
Serial Communications: Modbus® RTU, RS485, 9600 Baud.
Agency Approvals: CE, UL
DH Applications
• SCFM Flow in Ducts
• Air Flow for Industrial Ovens
• Filter Status
• Clean Room Pressure
• Fume Hood Air Flow
• Medical Room Pressures
• Static Pressures in Ducts or Buildings
• Damper Control
• Fan Control
