Dwyer Instruments DM DigiMag Series User manual

Series DM DigiMag®Differential Pressure Transmitter
Specications - Installation and Operating Instructions
Bulletin P-DMT
The Series DM DigiMag®Differential Pressure Transmitter senses the pressure
of air and compatible gases and sends a standard 4-20 mA output signal. The DM
housing is specically designed to mount in the same diameter cutout as a standard
Magnehelic® gage. A wide range of models are available factory calibrated to specic
ranges. The polycarbonate molded housing features integral pressure connections,
which reduces installation time. Digital push-button zero and span simplify calibration
over typical turn-potentiometers. A single push-button allows eld selection of 4 to 6
engineering units, depending on the range.
BENEFITS/FEATURES
• Reduced installation time through zero and span controls that provides quick and
easy calibration
• Fast and easy setup and calibration with push-button zero and span controls
• Immediate corrective action can be taken by local alerts via the easy-to-read LCD
display
• Reduces upgrade installation costs and simplies eld upgrade from a Magnehelic®
gage, as both use the same diameter cutout
APPLICATIONS
• Differential pressure across lters
• Fan control
• Static pressures in ducts or buildings
• Room pressurization monitoring
INSTALLATION
Location:
Select a clean, dry mounting location free from excess vibration where the temperature
will remain between -4 to 158°F (-20 to 70°C). Distance from the receiver is limited only
by total loop resistance. See Electrical Connections on the next page. The tubing
supplying pressure to the instrument can be practically any length required, but long
lengths will increase the response time slightly.
Position:
Transmitter pressure accuracy is not affected by orientation. If choosing a non-vertical
installation, ZERO the unit to remove any offset due to gravity.
Pressure Connections:
SPECIFICATIONS
Service: Air and non-combustible, compatible gases.
Wetted Materials: Consult factory.
Housing Material: Polycarbonate.
Accuracy: ±1% FSO for all ranges except 0.25 in w.c. @ ±2% FSO, and ranges at
or below ±0.1 in w.c. @ ±4% 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 Effect: 0.036% FS/°C (0.02% FS/°F).
Power Requirements: 10-35 VDC (2-wire).
Output Signal: 4-20 mA (2-wire).
Zero and Span Adjustments: Push-button.
Loop Resistance: 0 to 1250 Ω max.
Current Consumption: 21 mA max.
Electrical Connections: Screw-type terminals.
Process Connections: Male ports on side for 1/8˝, 3/16˝, 1/4˝, 5 mm, 6 mm ID
exible tubing.
Enclosure Rating: NEMA 4X (IP66).
Mounting Orientation: Not sensitive to position.
Size: 5˝ OD (127 mm) x 1.9˝ (48 mm) deep.
Weight: 7.04 oz (200 g).
Agency Approvals: CE.
DWYER INSTRUMENTS, INC.
P.O. BOX 373 • MICHIGAN CITY, INDIANA 46360, U.S.A.
Phone: [phone]
Fax: [phone]
www.dwyer-inst.com
e-mail: [email protected]
5 [127.00]
1 [25.40]
HIGH PRESSURE POR
T
LOW PRESSURE PORT
1/2 [12.70]
1-43/64
[42.34]
15/64
[5.84]
Two integral tubing connections are provided on the side of the
gage. They are sized to t 1/8˝, 3/16˝, 1/4˝, 5 mm, and 6 mm ID
exible tubing. Be sure the pressure rating of the tubing exceeds that of the operating
ranges.
NOTICE

MOUNTING
Panel Mount:
Provide a 4-9/16˝ diameter opening in panel. Insert gage and secure in place with
provided screws and mounting lugs.
Surface Mount:
Provide three 3/16˝ diameter holes in panel on a 4-1/8˝ diameter bolt circle. Cut an
opening for the terminal block as shown in Figure 2.
ELECTRICAL CONNECTIONS
Electrical connections are made to the terminal block located in the back of the
transmitter. Terminals are marked + and COM (see Figure 3 below).
Wire Length
The maximum wire length connecting the transmitter to the receiver depends on the
on the wire gage and the resistance of the receiver. When calculating loop resistance,
wiring should not contribute more than 10% of the receiver resistance. For runs over
1000´, choose a receiver with greater resistance. When wiring length is less than 100´,
22 AWG wire can be used.
2-Wire Operation
An external power supply delivering 10-35 VDC with minimum current capability of
40 mA DC (per transmitter) must be used to power the control loop. See Figure 4 for
connection of the power supply, transmitter, and receiver. The range of appropriate
receiver load resistance (RL) for the DC power supply voltage available is expressed
by the formula and graph in Figure 5. Shielded two wire cable is recommended for
control loop wiring. If grounding is required, use the negative side of the control loop
after the receiver.
SELECT UNIT OF MEASUREMENT
To select a unit of measurement, press and release the UNITS button to cycle through
the available options. The LCD will display the current selected unit.
Figure 1: Panel mount
Figure 4
Figure 5
Figure 2: Surface mount
Figure 3
[3] HOLES FOR #6 SCRE
W
EQUALLY SPACED ON
4-1/8 [104.78] B.C.
1-1/2 [38.10]
1 [25.40]
1 [25.40]
1 [25.40]
Do not exceed specied supply voltage ratings, as doing so will
result in permanent damage not covered by warranty. This unit is
not designed for 120 or 240 V AC line operation.
CAUTION
1500
1400
1300
1200
1100
1000
900
800
700
600
500
400
300
200
100
50
Total Receiver Resistance Ω
Maximum Value (1250)
R Max. =
0 5 10 13 15 20 25 30 35 40
L
Vps–10.0
20mA DC
Operating
Region
SERIES DM
PRESSURE
TRANSMITTER
-
+
RECEIVER
POWER
SUPPLY
10-35 VDC
-
+
+-

CALIBRATION
To calibrate the transmitter you will need three pieces of equipment:
1. A calibrated pressure source capable of generating a stable pressure value for
the maximum range of the unit under test
2. An instrument capable of validating the calibration pressure
3. An ammeter capable of measuring the current mA output from the unit under test
The transmitter is calibrated using the following procedure.
Preparing for Zero Calibration, Span Calibration, Response Time Calibration, or
Restore Factory Calibration Coefcients
To prepare the unit for zero or span calibration, response time calibration, or to restore
factory calibration coefcients, start by preparing the unit as instructed below:
1. Connect the ammeter and power supply, being careful to observe polarities.
2. Press both the ZERO and UNITS buttons simultaneously for 6 or more seconds,
or until “CAL” is displayed. Release both buttons.
3. The units indicator on the LCD should blink on and off. This indicates the gage
is ready for calibration or restoration of coefcients. The unit’s indicator will blink
for approximately 10 minutes, then stop blinking.
Zero Calibration
• Apply zero pressure to both ports.
• Press the zero button for 3 seconds. Release.
• The zero function will be processed 3 seconds after the button is released.
• The display will read “2Er” and then sequence back to the home display.
Span Calibration
The span calibration function allows the pressure value to be adjusted so that the
currently applied pressure is the maximum congured pressure. This will in turn set
the maximum analog output at the set pressure. It is recommended that the ZERO
function be applied before performing a span calibration.
• Apply the maximum desired pressure to the device.
• Press and hold the UNITS button for 3 seconds.
• The span function will be processed 3 seconds after the span button is released.
• The display will read “SPA” and then sequence back to the home display.
Response Time Calibration
Press both the “ZERO” and “UNITS” buttons simultaneously for 3 seconds to toggle
between fast (0 seconds) and dampened (4 seconds) response. The display will read
FST or SLO to indicate which mode is now selected.
Restore Factory Calibration
To restore the gage’s factory calibration coefcient:
• Press both the “ZERO” and “UNITS” buttons simultaneously for 6 seconds or until
“rSt” is displayed.
• The device will reboot after 5 or 6 seconds.
MAINTENANCE
Upon nal installation of the Series DM, no routine maintenance is required. The
Series DM is not eld serviceable and should be returned if repair is needed. Field
repair should not be attempted and may void warranty.
WARRANTY/RETURN
Refer to “Terms and Conditions of Sale” in our catalog and on our website. Contact
customer service to receive a Return Materials Authorization (RMA) number before
shipping the product back for repair. Be sure to include a brief description of the
problem plus any additional application notes.
This symbol indicates waste electrical products should not be disposed
of with household waste. Please recycle where facilities exist. Check with
your Local Authority or retailer for recycling advice.
For a positive span, apply pressure to the positive “+” port.
NOTICE
MODEL CHART
Model Range Model Range
DM-001
DM-002
DM-003
DM-004
DM-005
DM-007
DM-008
DM-019
DM-201
DM-202
DM-203
0.1 in w.c.
0.25 in w.c.
0.5 in w.c.
1 in w.c.
2 in w.c.
3 in w.c.
5 in w.c.
-0.05-0-0.20 in w.c.
±0.1 in w.c.
±0.25 in w.c.
±0.5 in w.c.
DM-052
DM-053
DM-056
DM-059
DM-252
DM-253
DM-256
DM-259
DM-082
DM-282
30 Pa
60 Pa
250 Pa
1250 Pa
±30 Pa
±60 Pa
±250 Pa
±1250 Pa
6 mm w.c.
±6 mm w.c.

Printed in U.S.A. 11/21 FR# 444617-00 Rev. 1©Copyright 2021 Dwyer Instruments, Inc.
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DWYER INSTRUMENTS, INC.
P.O. BOX 373 • MICHIGAN CITY, INDIANA 46360, U.S.A.
Phone: [phone]
Fax: [phone]
www.dwyer-inst.com
e-mail: [email protected]