The Series DHC Digihelic
®
possessing a digital display gage, control relay switches, and a transmitter with both
current and voltage outputs. Combining these 3 features allows the reduction of
several instruments with one product, saving inventory, installation time, and cost.
The Series DHC Digihelic
®
pressure, velocity, and volumetric flow applications reading in several commonly
used engineering units with optional unidirectional or bidirectional ranges. These
units achieve a 1.5% or better accuracy on extremely low ranges, and 0.5% accuracy
for ranges at or above 1 in w.c. Calibration can be performed in the field, making
maintaining its accuracy more manageble. Additionally, the Series DHC Digihelic
differential pressure controller includes 2 SPDT control relays with adjustable
deadbands. Programming the unit is simple using the built-in menu. With scalable
4-20 mA, selectable voltage process outputs, and selectable Modbus
communication, this controller can easily fit into your application.
INSTALLATION
Select a clean, dry location that is free from shock and vibration where temperature
limits will not be exceeded. Distance from the transmitter to the receiver is limited
only by total loop resistance. See WIRING section. The tubing feeding pressure to
the instrument can be practically any length required, but longer lengths will slightly
increase response time.
All standard models are calibrated for use in a vertical mounting position. The DHC
will perform properly when mounted at any angle but should be zeroed before use.
Pressure Connections
For installation convenience, there are two sets of 1/8˝ female NPT pressure ports;
one set is located on the back of the unit and the other is located on the side. Be sure
to seal the unused ports with the included pipe plugs (accessory A-330).
• Positive Pressure: Connect tubing to the HIGH PRESSURE port (indicated with a
"+" sign) and vent the LOW PRESSURE port (indicated with a "-" sign) to
atmosphere.
• Negative (Vacuum) Pressure: Connect tubing to the LOW PRESSURE port
(indicated with a "-" sign) and vent the HIGH PRESSURE port (indicated with a
"+" sign) to atmosphere. When operating this device in a dusty environment, install
an optional A-331 filter vent plug into the vented port to keep interior clean.
• Differential Pressure: Connect tubing from the higher source to the HIGH
PRESSURE port (indicated with a "+" sign) and from the lower source to the LOW
PRESSURE port (indicated with a "-" sign).
DWYER INSTRUMENTS, INC.
P.O. BOX 373 • MICHIGAN CITY, INDIANA 46360, U.S.A.
1.800.544.2843
Series DHC Digihelic
Specifications - Installation and Operating Instructions
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Differential Pressure Controller is a 3-in-1 instrument
differential pressure controller is the ideal instrument for
www.calcert.com
15
10
20
5
25
0
30
Differential Pressure Controller
®
1/8 FEMALE NPT HIGH
PRESSURE CONNECTION
1 [25.40]
1/8 FEMALE NPT LOW
PRESSURE CONNECTION
3x Ø3/16 [4.77] HOLES EQUALLY
SPACED ON A 4-1/8 [104.78] B.C.
SURFACE MOUNTING
1/2 [12.70]
SPECIFICATIONS
Service: Air and non-combustible, compatible gases.
Wetted Materials: Consult factory.
Housing Material: Polycarbonate.
Accuracy: ±0.5% FSO for all ranges, except 0.5 in w.c. @ ±1% FSO, and ranges at
or below ±0.25 in w.c. @ ±1.5% FSO.
Stability: < ±1% / year FSO.
Pressure Limits: Ranges > 1 in w.c.: 6 psi max operation, 6 psi burst; Ranges ≤ 1
in w.c.: 3.6 psi max operation, 6 psi burst.
®
Temperature Limits: -4 to 158°F (-20 to 70°C).
Thermal Effects: .02% FS / °F (.036% FS / °C).
Power Requirements: 12-28 VDC or 12-28 VAC 50 to 400 Hz.
or BACnet
®
Power Consumption: 3 VA max.
Output Signal: 4-20 mA (4-wire); 0-10 V, 0-5 V, 1-5 V, and 2-10 V (4-wire).
Communication: BACnet MS/TP or Modbus
Supported Baud Rate: 9600, 19200, 38400, 57600, 76800, 115200.
Device Load: 1/8 unit load.
Zero and Span Adjustments: Accessible via menus.
Response Time: 400 ms (damping set to 0).
Display: Backlit LCD display, LED setpoint indicators.
Electrical Connections: 15 pin male high density D-sub connection. 18˝ (46 cm)
cable with 15 conductors included.
Process Connections: 1/8˝ female NPT ports on side and back.
Enclosure Rating: NEMA 4X (IP66).
Mounting Orientation: Not position sensitive.
Size: 5˝ OD (127 mm) x 1.9˝ (48 mm) deep.
Weight: 8.8 oz (250 g).
Compliance: BTL, CE.
SWITCH SPECIFICATIONS
Switch Type: 2 SPDT relays.
Electrical Rating: 1 A @ 30 VAC/VDC.
Set Point Adjustment: Accessible via menus.
MODEL CHART
Model
Range
DHC-002
0.25 in w.c.
DHC-003
0.5 in w.c.
DHC-004
1 in w.c.
DHC-006
2.5 in w.c.
DHC-008
5 in w.c.
DHC-009
10 in w.c.
DHC-010
25 in w.c.
DHC-011
50 in w.c.
DHC-012
100 in w.c.
DHC-202
±0.25 in w.c.
DHC-203
±0.5 in w.c.
DHC-204
±1 in w.c.
DHC-206
±2.5 in w.c.
Phone: 219-879-8000
Fax: 219-872-9057
HIGH
PRESSURE
PORT
1 [25.40]
LOW
PRESSURE
PORT
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1/2 [12.70]
[5.84]
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[42.34]
®
RTU.
Model
Range
DHC-208
±5 in w.c.
DHC-209
±10 in w.c.
DHC-053
60 Pa
DHC-055
125 Pa
DHC-056
250 Pa
DHC-253
±60 Pa
DHC-255
±125 Pa
DHC-256
±250 Pa
DHC-082
6 mm w.c.
DHC-084
25 mm w.c.
DHC-282
±6 mm w.c.
DHC-284
±25 mm w.c.
www.dwyer-inst.com
e-mail: info@dwyermail.com
sales@calcert.com
Bulletin P-DHC
Ø5 [127.00]
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