The SERIES DH3 Digihelic® Differential Pressure Controller is a 3-in-1 instrument possessing a digital display gage, control relay switches, and a transmitter with current output all packed in the popular Photohelic® gage style housing. 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 1% full scale accuracy on ranges down to the extremely low 0.25" w.c. to 2.5" w.c. full scale. Ranges of 5" w.c. and greater maintain 0.5% F.S. accuracy. Bi-directional ranges are also available.
The Series DH3 Digihelic® controller allows the selection of pressure, velocity or volumetric flow operation in several commonly used engineering units. 2 SPDT control relays with adjustable deadbands are provided along with a scalable 4-20 mA process output.

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 reading; digital damping for smoothing erratic process applications; scaling the 4-20 mA process output to fit your applications range and field calibration.
Please see SERIES AT2DH3 for ATEX approved.

Approvals:
• CE Approval

Features:
• 3-in-1 instrument allows the reduction of several instruments with one product, saving inventory, installation time and money
• Secure menu program provides access to device operation only for the right skill level
• Full scale accuracy of 1% even on extremely low ranges, and 0.5% for ranges above 5 in w.c. provide for greater measurement precision

Applications:
• SCFM flow in ducts
• Filter status
• Static pressures in ducts or buildings
• Damper control
• Fan control

Specifications :

Service:	Air and non-combustible, compatible gases.
Wetted Materials:	Consult factory.
Housing Materials:	Die cast aluminum case and bezel.
Accuracy:	±1.5% for 0.25" and ±0.25" w.c. ranges. Ranges 0.5" to 5" w.c. and corresponding bi-directional (except ±2.5" w.c.) ±1%; All other ranges: ±0.5% @ 77°F (25°C) including hysteresis and repeatability (after 1 hour warm-up).
Stability:	< ±1% per year.
Pressure Limits:	Ranges ≤ 2.5 in w.c.: 25 psi; ±2.5", 5 in w.c.: 5 psi; 10 in w.c.: 5 psi; 25 in w.c.: 5 psi; 50 in w.c.: 5 psi; 100 in w.c.: 9 psi.
Temperature Limits	0 to 140°F (-18 to 60°C).
Compensated Temperature Limits:	32 to 122°F (0 to 50°C).
Thermal Effect:	0.020%/°F (0.036/°C) from 77°F (25°C). For 0.25" and ±0.25" w.c. ranges: ±0.03%/°F (±0.054%/°C).
Power Requirements:	12 to 28 VDC, 12 to 28 VAC 50 to 400 Hz.
Power Consumption:	3 VA max.
Current Consumption:	5 mA maximum
Output Signal:	4 to 20 mA DC into 900 Ω max.
Zero & Span Adjustments:	Accessible via menus.
Response Time:	250 ms (damping set to 1).
Display:	Backlit 4 digit LCD 0.4" height LED indicators for set point and alarm status.
Electrical Connections	15 pin male high density D-sub connection. 18" (46 cm) cable with 10 conductors included. 4' and 10' cables available.
Process Connections	1/8" female NPT. Side or back connections.
Mounting Orientation:	Mount unit in vertical plane.
Size:	5" (127 mm) OD x 3-1/8" (79.38 mm).
Weight:	1.75 lb (794 g).
Agency Approvals:	CE.
	SWITCH SPECIFICATIONS
Switch Type:	2 SPDT relays.
Electrical Rating:	1 A @ 30 VAC/VDC.
Set Point Adjustment:	Adjustable via keypad on face.