Series DHC Digihelic
®
Differential Pressure Controller
Specifications - Installation and Operating Instructions
Bulletin P-DHC
The
Series DHC Digihelic
®
Differential Pressure Controller
is a 3-in-1 instrument
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
®
differential pressure controller is the ideal instrument for
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
®
or BACnet
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).
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.
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
®
RTU.
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.
DWYER INSTRUMENTS, INC.
P.O. BOX 373 • MICHIGAN CITY, INDIANA 46360, U.S.A.
Phone: 219-879-8000
Fax: 219-872-9057
www.dwyer-inst.com
e-mail: [email protected]
1-3/8
[34.93]
53/64
[20.96]
1 [25.40]
HIGH
PRESSURE
PORT
LOW
PRESSURE
PORT
1 [25.40]
1/8 FEMALE NPT HIGH
PRESSURE CONNECTION
Ø5 [127.00]
1/2 [12.70]
3x Ø3/16 [4.77] HOLES EQUALLY
SPACED ON A 4-1/8 [104.78] B.C.
SURFACE MOUNTING
1/8 FEMALE NPT LOW
PRESSURE CONNECTION
1/2 [12.70]
1-43/64
[42.34]
15/64
[5.84]
MODEL CHART
Model
Range
Model
Range
DHC-002
DHC-003
DHC-004
DHC-006
DHC-008
DHC-009
DHC-010
DHC-011
DHC-012
DHC-202
DHC-203
DHC-204
DHC-206
0.25 in w.c.
0.5 in w.c.
1 in w.c.
2.5 in w.c.
5 in w.c.
10 in w.c.
25 in w.c.
50 in w.c.
100 in w.c.
±0.25 in w.c.
±0.5 in w.c.
±1 in w.c.
±2.5 in w.c.
DHC-208
DHC-209
DHC-053
DHC-055
DHC-056
DHC-253
DHC-255
DHC-256
DHC-082
DHC-084
DHC-282
DHC-284
±5 in w.c.
±10 in w.c.
60 Pa
125 Pa
250 Pa
±60 Pa
±125 Pa
±250 Pa
6 mm w.c.
25 mm w.c.
±6 mm w.c.
±25 mm w.c.
®
www.calcert.com
1.800.544.2843
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