Description
The DPG1000L is a 2-wire pressure transmitter with
digital display. It is powered by the 4-20 mA current loop
and produces a true analog output signal. The output is
filtered to improve noise immunity. The temperature
compensated piezoresistive transducer features 316
stainless steel wetted parts.
Installation Precautions
Tighten/remove with wrench on hex fitting only. Do not
attempt to rotate gauge by turning housing. Use fittings
appropriate for the pressure range of the gauge. Do not
apply vacuum to gauges not designed for vacuum
operation. NEVER insert objects into the gauge port or
blow out with compressed air. Permanent damage not
covered by warranty will result.
Electrical Connection
Connection to the DPG1000L is made with the 2-wire
cable at the gauge rear. Connect the loop (+) supply to
the RED lead and the loop (–) supply to the BLACK
lead. Reversing the connections will not harm the gauge
but the gauge will not operate with incorrect polarity.
Loop Voltage
Select a loop power supply voltage and total loop
resistance so that when the loop current is 20 mA, the
gauge will have at least 8 VDC at its terminals. Too large
a loop resistance will cause the gauge output to “limit” or
saturate before reaching its full 20 mA output. See graph
below.
The minimum loop supply voltage may be calculated
from the formula:
Vmin = 8V + (20mA x Total loop resistance)
If the terminal voltage of the gauge falls below about 7.8
VDC erroneous reading or erratic operation may occur.
This is indicates that the loop supply/resistance may not
have adequate headroom for reliable operation. This
should never occur in normal use. If it does, check loop
supply and resistance.
Operation
The DPG1000L is designed for continuous operation.
Warm-up time is negligible. The display will show the
system pressure/vacuum, and the loop current also will
be proportional to the system pressure/vacuum; 4 mA =
Zero or low end, 20 mA = Span, full-scale or high end.
TEST Button
When the TEST button is held depressed, the display
and loop current are switched to a test level determined
by the setting of the Test potentiometer. This test mode
will allow setup and testing of the current loop by
switching to this test level whenever desired without
having to alter the system pressure.
To set the test output level, see gauge label for location
of Test potentiometer. Press and hold the front-panel
TEST button and adjust the Test potentiometer to set the
display and loop current to the desired test level.
Calibration
See gauge label for location of individual controls to
adjust the zero and span of the display.
GAUGE reference units may be re-zeroed without
affecting the span calibration. The gauge port must be
open to the ambient with no pressure or vacuum
applied. Adjust the Zero control until the gauge reads
zero with the minus (–) sign occasionally flashing.
Span calibration should only be attempted if the user
has access to a pressure reference of known accuracy.
The calibration equipment should be at least four times
the gauge accuracy. Zero calibration must be done
before span calibration. Record readings at three to five
points over the range of gauge and adjust span control
to minimize error and meet specifications.
ABSOLUTE reference gauges require vacuum
generation and atmospheric pressure measurement
equipment for accurate calibration and thus are more
difficult to calibrate in the field. Gauges may be returned
to Omega Engineer ing for recalibration. N.I.S.T.
traceability is available.
The DPG1000L has internal controls to adjust the
agreement between the displayed value and the 4-20
mA loop current. These are set at the factory and should
not normally be adjusted. If adjustment is necessary, the
display zero/span must be accurately set first. Then,
after removing the rear cover, the Loop Zero and Loop
Span controls may be trimmed for 4.00 mA of loop
current at the low end of the range, and 20.00 mA at the
high end of the range, respectively. Accurate pressure
generation and measurement and current measurement
equipment are required to successfully complete this
calibration.
Digital Pressure Gauges
DPG1000L Series, 4-20mA Current Loop Powered
INSTRUCTION
SHEET
M3360/1001
SPECIFICATIONS
Ranges & Resolution
30.0 inHg vacuum, ±15.00, 3.00, 5.00, 15.00, 30.0 psig
100.0, 199.9, 300, 500, 1000, 3000, 5000 psig
Absolute reference: 15.00, 100.0 psia
Optional Units
Most engineering units such as kPa, atm, bar, mbar,
inHg, mmHg, inH
2
O, ftH
2
O, torr, kg/cm
2
, cmH
2
O, oz/in
2
Display (type, size, update rate)
Ranges up to 1999: 3
1
/
2
digit LCD,
1
/
2
" digit height
3000 and 5000 psi ranges: 4 digit LCD, 0.4" digit height
3 readings per second nominal display update
Accuracy (linearity, hysteresis, repeatability)
±0.25% of full scale or better, ±1 least significant digit
Output Characteristics
True analog output, 50 millisecond typical response time
Loop Supply Voltage
Any DC supply/loop resistance that maintains 8 to 32
VDC at gauge terminals. Reverse polarity protected.
Low Loop Warning
(below approximately 7.8 VDC)
Ranges up to 1999: Colon appears
3000 and 5000 psi ranges: All decimal points flash
Controls & Location
TEST button sets output to test level, 0-100% range
Internal potentiometers: Loop 4 mA and 20 mA
Ranges up to 1999: Front zero, span & test pots
3000 and 5000 psi ranges: Top zero, span & test pots
All models: Non-interactive zero & span, ±10% range
Temperature Stability (relative to 77°F or 25°C)
±1% FS for offset & span, 32 to 158°F (0 to 70°C) typical
±2% FS for offset & span, 32 to 158°F (0 to 70°C) typical
for 3 and 5 psi ranges
Weight (approximate)
Gauge: 9 ounces, shipping weight: 1 pound
Housing
Extruded aluminum case, light gray epoxy powder coated
Black polycarbonate cover, front and rear gaskets
Pressure/Vacuum Connection & Material
1
/
4
" NPT male, all wetted parts are 316 SS
Overpressure & Burst
5000 psig for 3000 psig range
7500 psig for 5000 psig range
All others 2x rated pressure minimum
Burst: 4x rated pressure minimum or 10,000 psi,
whichever is less
Storage temperature:
–40 to 203°F (–40 to 95°C)
Operating temperature:
–4 to 185°F (–20 to 85°C)
Compensated temperature:
32 to 158°F (0 to 70°C)
1
/
4
" NPT
3.38"
0.75"
PSIG
Span
Zero
1
/
4
" NPT
2.88"
3.38"
0.75"
1.65"
PSIG
Turn at
hex
fitting
only!
Zero
Span
Ranges up to 1999
3000 and 5000 psi ranges
Zero, Test, Span
OMEGA Engineering Inc./Made in USA
OMEGA Engineering Inc./Made in USA
0.75"
3 ft long,
2-conductor,
22 AWG
shielded cable
TEST
Test
TEST
1400
1200
1000
800
600
400
200
0
Max Loop Resistance (Ohms)
8
12
16
20
24
28
32
Loop Supply Voltage (DC)
Voltage Compliance for
4-20 mA Current Loop
Test
