Omega Products PX293 Installation Manual

Page 1
User’s Guide
omega.com
®
www.omega.com
™
PX293 Series
Liquid Low Differential Pressure Transmitter
Page 2
omega.comomega.com
®
™
Page 3
INSTALLATION OF PRESSURE TRANSMITTERS

PX293 Series

The PX293 Series tr ansmitters meas ure low dif ferential press ures of gases or liquids compat ible with 316 type stainless steel. The normal oper ating t emperature range is from 0°C to 50°C (32°F to 122°F), and the normal humidity range from 10% to 90% R.H.
Remove the cover to gain access to the two mounting holes. These holes are suitable for #8 (4mm) max. screws.
Connections to the fluid lines are by means of 1/8-28 Female NPT ports. Make sure the operating static pressure does not exceed the values shown in the table below.
The maximum safe momentary overpressure at any port should not exceed 2x the maximum operating static pressure
PRES. CODE
31E 32E 33E 34E 35E 36E 37E 38E
.
STANDARD PRESSURE RANGES
ENGLISH UNITS METRIC UNITS
DIFF.
PRESS.
psid
0 - 6 0 - 10 0 - 15 0 - 30 0 - 60
0 - 100 0 - 150 0 - 200
OPER. STATIC PRESS
psi
0 - 100
0 - 300
PRES. CODE
31P 32P 33P 34P 35P 36P 37P 38P
DIFF.
PRESS.
0 - 50
0 - 75 0 - 100 0 - 200 0 - 500 0 - 750
0 - 1000 0 - 1500
kPa
OPER.
STATIC
PRESS.
kPa
0 - 700
0 - 2000
PRES. CODE
31B 32B 33B 34B 35B 36B 37B 38B
DIFF.
PRESS.
bar
0 - 0. 5
0 - 0.75
0 - 1. 0 0 - 2. 0 0 - 5. 0
0 - 7. 5 0 - 10.0 0 - 15.0
OPER.
STATIC
PRESS.
bar
0 - 7. 0
0 - 20
Electrical connections are by means of pluggable terminal strips, rated at 250 Vac, with a wire range from 14 to 26 AWG.
Zero and Span Adjustment
The transmitter may be re-zeroed and re-spanned if a permanent drift is noted. Vent both pressure ports to atmosphere before recalibrating the transmitter,
A. Voltage Output Units (PX293-XX XXD5V): Connect a voltmeter across the signal terminals
(see Figure 1 or Figure 2, respectively), and adjust the ZERO po-tentiometer R2 until the voltage reads 0.01V. Nex t, apply the full rat ed differential pr essure to the high pressure port and adjust the SPAN potentiometer R1 until the output reading is 5.00V.
B. Current Output Units (PX293-XXXXDI): Connect an ammeter in the loop (see Figure 3 or
Figure 4, respectively), and adjust the ZERO potentiometer R2 until the ammeter reads
4.00mA. Next, apply the full rated differential pr essure to the high press ure port and adjust the SPAN potentiometer R1 until the output re ad ing is 20.00 mA .
Re-spanning the transmitter requires a source of pressure of satisfactory accuracy. Check the zero reading again for accuracy, and repeat the above steps if necessary. Potentiometer R3 should not normally be adjusted unless one of the pressure sensors has been replaced and the span accuracy of the instrument is affected by changes in the static pressure.
PX293 Series M-3486 / 0899
Page 4
VOLTAGE OUTPUT UNITS
(PX293-XXXXD5V)
CURRENT OUTPUT UNITS
(PX293-XXXXDI)
This transmitter is powered by an external power supply between 11 and 32Vdc (14Vdc minimum for 10 V ou tp ut), th e cur r ent drawn is less than 10mA.
The output voltage is limited to about 5.3V for the 0-5V transmitter and about 10.6V for the 0-10V transmitter if the differential pressure exceeds the range of the transmitter. Short-circuiting the signal terminals will not damage the transmitter. Figure 1 shows typical transmitter wiring
.
This is a 2-wire, 4-20 mA pressure trans­mitter which requires a n external DC power supply of 11 to 32 Vdc to power the loop. The supply voltage should not exceed 32 Vdc (see Figure 2).
Figure 2
The following graph (s ee Fig ur e 3) illustrates the maximum wire and receiver resistances as a function of supply voltage. For example: the total loop resistance should not exceed 650 Ohms for a typical supply voltage of 24 Vdc
.
Figure 1
CAUTION: REVERSAL OF THE “VDC IN”
AND “SIGNAL OUT” MAY RESULT IN
PERMANENT DAMAGE TO THE
TRANSMITTER.
Figure 3
The standard transmi tter is curr ent-limit ed t o about 3.85 mA at the low end and 25 mA at the high end. An interna l diode protects the transmitter against r eversal of po larity (t here is no current flowing t hrough the loop if the leads are reversed).
PX293 Series M-3486 / 0899
Page 5
MADE IN
Page 6
Where Do I Find Everything I Need for
Process Measurement and Control?
OMEGA…Of Course!
TEMPERATURE
MU
Thermocouple, RTD & Thermistor Probes, Connectors, Panels & Assemblies
MU
Wire: Thermocouple, RTD & Thermistor
MU
Calibrators & Ice Point References
MU
Recorders, Controllers & Process Monitors
MU
Infrared Pyrometers
PRESSURE, STRAIN AND FORCE
MU
Transducers & Strain Gages
MU
Load Cells & Pressure Gages
MU
Displacement Transducers
MU
Instrumentation & Accessories
FLOW/LEVEL
MU
Rotameters, Gas Mass Flowmeters & Flow Computers
MU
Air Velocity Indicators
MU
Turbine/Paddlewheel Systems
MU
Totalizers & Batch Controllers
pH/CONDUCTIVITY
MU
pH Electrodes, Testers & Accessories
MU
Benchtop/Laboratory Meters
MU
Controllers, Calibrators, Simulators & Pumps
MU
Industrial pH & Conductivity Equipment
DATA ACQUISITION
MU
Data Acquisition & Engineering Software
MU
Communications-Based Acquisition Systems
MU
Plug-in Cards for Apple, IBM & Compatibles
MU
Datalogging Systems
MU
Recorders, Printers & Plotters
HEATERS
MU
Heating Cable
MU
Cartridge & Strip Heaters
MU
Immersion & Band Heaters
MU
Flexible Heaters
MU
Laboratory Heaters
ENVIRONMENTAL MONITORING AND CONTROL
MU
Metering & Control Instrumentation
MU
Refractometers
MU
Pumps & Tubing
MU
Air, Soil & Water Monitors
MU
Industrial Water & Wastewater Treatment
MU
pH, Conductivity & Dissolved Oxygen Instruments
PX293 Series M-3486 / 0899
Loading...