
ELECTRICAL TERMINATION
Wiring: 2-Wire - 4 to 20 mA (Current Output) and Remote Zero
The Series WWDP when configured as a current output transducer is a
true 2-wire, 4-20 mA current output device and delivers rated current into
any external load of 0-1000 ohms.
When configured as a 4-20 mA current output device, the current flow is
in one direction only. PLEASE OBSERVE POLARITY.
We suggest that an electrical cable shield be connected to the system’s
loop circuit ground to improve electrical noise rejection.
Min. Supply Voltage: 12 + .02 x (Resistance of receiver plus line)
Max. Supply Voltage: 30 + .004 x (Resistance of receiver plus line)
Note: The Zero terminals, connected to digital output, provide contact closure
relay for automatic reset to zero pressure by the monitoring system. CAUTION:
ZERO input is for dry contact, do not apply voltage to ZERO Terminals.
©Copyright 2007 Dwyer Instruments, Inc. Printed in U.S.A. 9/07 FR# R1-443565-00 Rev.1
A B C D A B C D
ZERO
OUTPUT
RANGES
DC Power
Supply
Controller
Current
(4-20 mA)
Relay
EXC. OUT COM
A B C D A B C D
BAR
A.REV
SLOW
BI-DIR
SWAP
PSI
NORM
FAST
UNI-DIR
NORM
WWDP-1
WWDP-2
WWDP-3
50
100
250
25
50
125
10
20
50
5
10
25
4-20 0-5 0-10 1-5
Figure 2
DC/AC
Power Supply
Controller
Voltage
Relay
ABCD ABCD
ABCD
ABCD
WWDP-1
WWDP-2
WWDP-3
50
100
250
25
50
125
10
20
50
5
10
25
4-20 0-5 0-10 1-5
PSI
NORM
FAST
UNI-DIR
NORM
BAR
A.REV
SLOW
BI-DIR
SWAP
EXC. OUT COM
Figure 3
Important: Prior to putting the unit into service, press the “Zero”
button, then use the “Range Selection Switch” to select a range.
After selecting a range, press the “Zero” button again. For
instructions regarding operation of the Series WWDP, please refer
to the following, Operation.
OPERATION
Range Selection Switch Auto Zero Button Electrical Output Configuration
Electrical Connections
WWDP-1
WWDP-2
WWDP-3
A
50
100
250
B
25
50
125
C
10
20
50
D
5
10
25
A B C D A B C D
ZERO
A
4-20
B
0-5
C
0-10
D
1-5
PSI
NORM
FAST
UNI-DIR
NORM
BAR
A.REV
SLOW
BI-DIR
SWAP
4-20 MA REMOTE ZERO
ETC. OUT COM
Figure 4
Range Selection Switch: The unit is set to the highest range when
calibrated. To select the other ranges, slide the switch to the right.
Important: Push “zero” button after installing the Series WWDP,
and after changing range.
Auto Zero Button: Press and hold the “ZERO” push-button for 2 seconds
to automatically reset zero or provide contact closure on “Remote Zero”,
see Figure 2 and Figure 3.
Electrical Output: The unit is set to 4-20 mA. To select another output,
move the slide switch to the right.
Electrical Connections: Electrical termination for power supply, 3-wire voltage
output and 2-wire true 4-20 mA current output, and remote zero wiring.
A.Rev/NORM: A.REV: Analog Reverse: When in reverse mode, the output
increases when the differential pressure decreases and decreases as pressure
increases. NORM: When in Normal mode, output increases as pressure
increases and decreases as pressure decreases.
SLOW/FAST: When Slow mode is selected, 5-second averaging is provided
for surge damping.
BI-DIR/UNI-DIR: Select UNI-Directional or BI-Directional mode. Unidirectional
mode measures from 0 to full scale differential pressure. Bidirectional mode
measures pressure from minus 1/2 of full scale to plus 1/2 of full scale differential
pressure. Output will read 1/2 full scale when differential pressure is zero.
SWAP/NORM: Jumper selectable Port Swap feature eliminates costly
replumbing when incorrectly installed or replaced. Go from NORMAL to SWAP
and the jumper makes the “HI” Port “LO” and the “LO” Port “HI”.
RETURNING PRODUCTS FOR REPAIR
Please contact Dwyer Instruments, Inc. before returning unit for repair to review
information relative to your application. Many times only minor field adjustments
may be necessary. When returning a product to Dwyer Instruments, Inc., the
material should be carefully packaged and shipped.
Upon final installation of the Series WWDP Differential Pressure Transducer,
no routine maintenance is required. A periodic check of system calibration
is recommended. The Series WWDP is not field serviceable and should be
returned if repair is needed (field repair should not be attempted and may
void warranty). Be sure to include a brief description of the problem plus
any relevant application notes. Contact customer service to receive a
return goods authorization number before shipping.
Note: Please remove any pressure fittings and plumbing that you have installed
and enclose any required mating electrical connectors and wiring diagrams.
Wiring: 3-Wire, 0 to 5, 0 to 10, 1-5 VDC and Remote Zero
The Series WWDP when configured for voltage output is a 3-wire circuit
device with three terminals available for wiring. The -Excitation and -Output
are commoned on the circuit.
Caution: Do Not Connect “+” exc to “+” out.
The Series WWDP can operate from 12-30 VDC (18-28 VAC) nominal
output power supply.
NOTE: The ZERO terminals, connected to digital output, provide a contact
closure relay for automatic reset to zero pressure by the monitoring
system. CAUTION: ZERO input is for dry contact, do not apply
voltage to ZERO Terminals.
DWYER INSTRUMENTS, INC.
Phone: 219/879-8000 www.dwyer-inst.com
P.O. BOX 373 • MICHIGAN CITY, INDIANA 46361, U.S.A. Fax: 219/872-9057 e-mail: info@dwyer-inst.com
Installation of the Series WWDP is now complete.
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