Dwyer PI - Manual

PROXIMITY CONTROLS
Phone: 219/879-8000 www.dwyer-inst.com
A DIVISION OF DWYER INSTRUMENTS, INC. Fax: 219/872-9057 e-mail: [email protected]
P.O. BOX 373 • MICHIGAN CITY, INDIANA 46360, U.S.A.
Bulletin V-PI
Specifications - Installation and Operating Instructions
Model PI Pressure To Current Transducer
SPECIFICATIONS
Service: Clean dry air filtered to 40 microns.
Input Signal: 3 to 15 psig and 3 to 27 psig.
Input Capacitance: 2 wire: 700 ƒ, standard; Voltage: 5k ƒ min.
Output: 2-wire: 4 to 20 mA.
Linearity: ±0.15% of span.
Hysteresis: ±0.15% of span max.
Accuracy: ±0.15% of span guaranteed; ±0.10% of span typical.
Includes combined effects of linearity, hysteresis and repeatability
errors.
Repeatability: ±0.10% of span; ±0.03% of span typical.
Response Time: 10 m sec to 99% of step change.
Power Requirements: 10 to 42 VDC.
Temperature Stability: Span and Zero: ±0.007% of span per °F max.
deviation from 77°F calibration.
Temperature Limits:
Operating: -40 to 167°F (-40 to 75°C);
Storage: -60 to 185°F (-50 to 85°C).
Calibration Adjustments: Non-interactive, multi-turn span and zero
potentiometers with approximately ±10% of span adjustment range.
Connections:
Signal Air: 1/8˝ NPT female;
Electrical Wiring: Miniature terminal block accepts solid or stranded
wire up to 14 AWG.
Weight: 0.5 lb (0.2 kg).
The Model PI Pressure To Current Transducer converts a pneumatic
input pressure to an accurately proportional output current with
uncompromising accuracy and durability. The PI serves in high-density
and panel-mounted applications. The rugged PI transducer offers a high
density DIN rail adapters and is space saving with easy plug-in
installation.
CALIBRATION
All PI transducers are fully calibrated at the factory to the output as
ordered. It may be advisable to confirm that the calibration was
maintained during shipment for maximum accuracy. Easily accessible
span and zero screws are located on the front panel. They are multi-turn
potentiometers with slip clutches at the ends of travel that can provide
±20% of span adjustability. Clockwise movement increases output on
both potentiometers.
INSTALLATION/WIRING
To connect the DIN rail adapter to the transducer, match the connections
together and tighten the screw to secure a snug fit. The PI is a “floating”
transducer and consequently may tolerate a single ground anywhere in
the 2-wire loop, with the single load placed anywhere as well. In most
instances, the loads should be placed in the negative leg, although it isn’t
necessary. An earth ground can be placed on either end of the load, but
may prefer to have the negative terminal of the supply earthed as well.
Care must be taken to ensure the polarity of the input connections is
correct regardless of where the loads or ground is placed. An inadvertent
reversing of polarity will not damage the PI, but it will not function until the
wiring is corrected. Proper wiring on the adapter uses the positive out
and the negative out terminals. The positive end of the power supply is
connected to the positive out terminal. The negative end of the power
supply is connected to the negative out terminal. For measurements,
place the reader between the positive out and the negative out wires. In
all instances, current flow enters at the positive terminal and exits at the
negative terminal. Refer to the figure to the on the next page.
17/32
[13.46]
3
[76.20]
1-63/64
[50.47]
3/4
[19.05]
5/16
[7.75] 1
[25.40]
PRESSURE INLET
1/8˝ NPT
3
[76.20]
3/4
[19.02]
3-7/16
[87.12]
45/64
[17.78]
5-25/32
[146.84]
5-3/8
[136.66]
MODEL NO. PI-X
SUPPLY: 10-42 VDC MAX. TEMP: 75°C
INPUT:X-XX PSIG
OUTPUT: 4 TO 20 mA SERIAL NO: XX-XXXX
TAG NO: XXX-XXXX P R O X IM IT Y C O N T R O L S
A D IV O F D W Y E R I N S T R U M E N T S , IN C
M IC H IG A N C IT Y , IN U S A
This unit is only to be used with dry instrument air filtered to 40
micron. Excessive moisture or chemical contaminants can
damage internal components.
CAUTION
The PI Transducer can withstand over-pressurization of three
(3) times the rated full scale without recalibration and four (4)
times the full scale without failure.
CAUTION
This unit can tolerate a maximum of 100 VDC at the input
terminals indefinitely, although operation within the
specifications is only guaranteed with power supplies between 10 and 42 VDC.
CAUTION
Do not subject this transducer to a temperature above 180°F
(82.2°C) or below -40°F (-40°C). CAUTION