Dwyer DPW - Manual (Page 4)

To eliminate the possibility of noise interference, use a separate cable entry for the
DC power and analog signal lines (pins L, M, K on “M16” connector).
2.2.3 Flow Sensor Pulse Output Signals Connections
Pin C -------- (+) Flow Sensor Pulse Output (active), 3.3Vdc
Pin B ------------ DC Power (-), Digital Common
2.2.4 Programmable Optically Isolated Output Signals Connections
Optocoupler #1 (pins F and G):
Pin G ------------ Plus (-) (passive)
Pin F ------------ Plus (+) (passive)
Optocoupler #2 (pins H and J):
Pin H ------------ Plus (+) (passive)
Pin J ------------ Plus (-) (passive)
2.2.5 Communication Parameters and Connections
The digital interface operates via RS485 (optional RS-232) and provides access to
applicable internal data including: flow, temperature, totalizers and alarm settings,
flow linearizer table, fluid density and engineering units selection.
Communication Settings for RS-485/RS-232 communication interface:
Baud rate: ------------ 9600 baud
Stop bit: ------------ 1
Data bits: ------------ 8
Parity: ------------ None
Flow Control: ------------ None
RS-485 communication interface connection:
The RS485 converter/adapter must be configured for: multidrop, 2 wire, half duplex
mode. The transmitter circuit must be enabled by TD or RTS (depending on which
is available on the converter/adapter). Settings for the receiver circuit should follow
the selection made for the transmitter circuit in order to eliminate echo
.
Pin E ------------ RS-485 T(+) or R(+)
Pin D ------------ RS-485 T(-) or R(-)
Pin B ------------ RS-485 GND (if available)
RS-232 communication interface connection:
Crossover connection has to be established:
Pin E ------------ RS-232 TX
(pin 3 on the DB9 connector)
Pin D ------------ RS-232 RX
(pin 2 on the DB9 connector)
Pin B ------------ RS-232 SIGNAL GND
(pin 5 on the DB9 connector)
2.3 - SPECIFICATIONS
Service: Liquids compatible with wetted materials.
Wetted Materials:
DPW-XP: Polypropylene and fluoroelastomer O-rings, PVDF and nickel
tungsten carbide paddlewheel, acrylic lid.
DPW-XT: PVDF and fluoroelastomer O-rings, PVDF and zirconia ceramic
paddlewheel, PVDF lid; Bearings: PVDF sapphire.
Accuracy: ±1% FS.
Repeatability: ±0.25% FS.
Response Time: 1 second above 10% of FS, 2 seconds below 10% of FS.
Output Signal: Linear 0 to 5 VDC (3000 Ω min. load impedance); 4 to 20 mA (500
Ω max. loop resistance).
Pulse Output: 3.3 VDC, 3K min. load impedance.
Digital Interface: RS-232; RS-485.
Temperature Limits: 14 to 140°F (-10 to 60°C).
Pressure Limit: 10 bar (150 psig).
Power Requirements: 11 to 26 VDC.
Display: 2 row, 16 character LCD with backlight (optional).
Process Connections: Female NPT.
Weight: 1.60 lb (0.73 kg).
The flow sensor pulse output is self-powered (open drain,
pulled up with 10K resistor to internal 3.3Vdc rail). Do NOT
connect an external voltage source to the pulse output signals. Use load with
input impedance more than 30K is recommended.
WARNING
Optically isolated outputs require application of DC voltage
across terminals. Do not exceed maximum allowed limits for
voltage and current provided below:
WARNING
Example
Series
Orifice Size
(Flow Range)
Material Lower
Block
Seals
Display/Keypad
RTD Option
Output Signal
Digital Interface
DPW
DPW 05
05
10
17
35
P
P
T
E
E
T
B
V
L
N
L
N
N
R
A
A
B
2
2
5
DPW-05-ELN-A2
Flow Transmitter
0.04 to 5 gal/min (0.15 to 18.9 L/min)
0.08 to 10 gal/min (0.3 to 37.6 L/min)
0.15 to 17 gal/min (0.6 to 64.4 L/min)
0.35 to 35 gal/min (1.3 to 132.5 L/min)
Polypropylene
PVDF
EPDM
PTFE
Buna-N
Fluorelastomer
No Display/No Keypad
LCD/Keypad
No RTD
RTD
0 to 5 VDC
4 to 20 mA
RS-232
RS-485
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