Omega Products DPG1000ADA Installation Manual

Digital Pressure Gauges

DPG1000ADA Series, Low Voltage AC/DC Powered
with Dual Alarm Relays

INSTRUCTION

MANUAL

M3362/1001

Description

The DPG1000ADA pressure gague circuitry includes dual mechanical
relay alarm outputs with fully adjustable setpoints in a standard HI/LO
alarm configuration. The DPG1000ADA alar ms are easy to set up and
use. Bicolor LEDs on the front panel (green = nor mal, red = alarm)
provide a visual indication of alarm status. Setpoint 1 and Setpoint 2
buttons allow viewing the setpoints on the gauge display without
disrupting normal operation. To test system installation and operation, a
front-panel TEST button, when pressed, toggles the alarm output status
independent of system pressure.

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

NEVER connect the gauge power wires directly to 115 VAC or

permanent damage not covered by warranty will result.
The two-conductor cable at the gauge rear is for the gauge power

supply.This cable has one RED and one BLACK lead. Since the gauge
will operate on either AC or DC power, there is no need to observe
polarity; simply connect an AC supply of 8 to 24 VAC, 50/60 Hz, or a DC
supply of 9 to 32 VDC to the two wires to activate the gauge. Since the
type and magnitude of the supply voltage have negligible effect on
gauge calibration or accuracy, an unregulated AC or DC power source
can be used, however if the gauge supply voltage falls below 8 VAC
RMS or 9 VDC, erratic operation or erroneous readings may occur.

The larger 6-conductor cable is for the alarm relay contact outputs.This
cable’s color code is as follows:

SETPOINT 1

Normally Closed (NC) BLACK
Common (C) RED
Normally Open (NO) WHITE

SETPOINT 2

Normally Closed (NC) GREEN
Common (C) BROWN
Normally Open (NO) BLUE

Operation

The gauge is powered ON whenever a supply voltage is applied.Warm­up time for full accuracy is negligible.

In normal operation, the system pressure is displayed on the gauge
LCD.The DPG1000ADA circuitry also compares the system pressure to
two independent setpoint levels; Setpoint 1 and Setpoint 2. These
setpoint levels may be viewed by pressing either the SP1 or SP2
buttons on the front of the unit. Normal operation of the alarm outputs is
not affected by pressing SP1 or SP2.

Alarm status is easily seen on the two alarm indicator LEDs in the
corner of the SP1 and SP2 buttons.A GREEN indication is a normal or

non-alarm condition; RED is an abnormal or alarm condition.
If a particular setpoint is factory configured as a HI alarm, the

DPG1000ADA will provide a RED alarm indication when the system
pressure exceeds the setpoint. If a par ticular setpoint is factory
configured as a LO alarm, the DPG1000ADA will provide a RED alarm
indication when the system pressure falls below the setpoint.

Setting Alarms

To access alarm SP1 and SP2 controls, lift the calibration label on the
top of unit and locate the proper potentiometer as indicated by the
gauge rear label.

Pressing SP1 or SP2 will switch the display to show and allow adjusting
of the corresponding setpoint.

To adjust alarm Setpoint 1, press and hold the SP1 button. When
holding the SP1 button, the display will show the current setting for
Setpoint 1. Turn the top-accessible Setpoint 1 control. Repeat the
procedure by pressing and holding the SP2 button to adjust Setpoint 2.

It is allowable to set the LO alarm to a higher pressure than the HI
alarm.

Test Button

For system setup, testing, and troubleshooting, the TEST button is
provided. This button, when pressed, toggles the current state of the
alarm outputs. Therefore the alarm outputs may be “exercised” on
demand without the need to vary the system pressure to test devices,
annunciators, etc.connected to these outputs.

Calibration

These gauges are factory calibrated and normally do not require
recalibration before being put into service.

If calibration is required, lift calibration label on the top of unit to access
the Zero and Span controls.

For GAUGE reference units the setting of the Zero control is correct
when the gauge reads zero, with the “–” sign occasionally flashing,
when the pressure port is open to the ambient. Zero calibration must be
done before span calibration is attempted. Since the calibration
potentiometers are non-interactive, gauge reference units may be
rezeroed without affecting the span.

Span calibration should only be done when a pressure reference of
known accuracy is available.The calibration equipment accuracy should
be better than 4 times the accuracy of the gauge. 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.

Calibration of ABSOLUTE reference units is more difficult and is not
recommended in the field, unless the user has access to equipment
required to calibrate absolute-reference units, such as vacuum
generation and atmospheric pressure measurement equipment.

Gauges can be returned to Omega Engineering for recalibration. NIST
traceability is available.

SPECIFICATIONS

Standard ranges

30.0 inHg vacuum, ±15.00, 3.00, 5.00, 15.00 psig

30.0, 100.0, 199.9 psig
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, inH2O, ftH2O, torr, kg/cm2,
cmH2O, oz/in

2

Display (type, size, update rate)

Ranges up to 1999: 3

1

/2 digit LCD, 1/2" digit height
3000 & 5000 psi ranges: 4 digit LCD, 0.4" H digits
3 readings per second nominal display update

Accuracy (linearity, hysteresis, repeatability)

±0.25% of full scale or better, ±1 least significant
digit

Temperature stability(rel. 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

Alarm deadbands (hysteresis)

1% of of full scale

Alarm outputs

Dual form C (SPDT) relay contacts
Individual Setpoint 1 and Setpoint 2 settings via
top-accessible multiturn potentiometers
HI/LO alarm configuration standard
Relay contacts rated 1A/24VDC, 0.5A/115VAC,
non-inductive

Alarm indicators

Bicolor (red/green) LEDs on front panel

Test function

Front panel TEST button toggles both SP1 and
SP2 alarm status, independent of pressure input
to allow testing of system operation.

Alarm response time

100 milliseconds typical

Calibration controls

Display zero/span, non-interactive, ±15% range;
Setpoint 1 and Setpoint 2, 0-100% range;
top-accessible, multiturn potentiometers

Power

8 to 24 VAC 50/60 Hz or 9 to 32 VDC, 1.0 watt
maximum power consumption.Optional wall­mount power supply available to operate on
115VAC.

Electrical connection

3 foot long, 2-conductor 22AWG cable for power
3 foot long, 6-conductor 22AWG cable for alarm
contacts

Weight (approximate)

Gauge: 9 ounces, shipping weight: 1 pound

Housing material

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 316SS

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)

Using the DPG1000 Alarm Outputs

Alarm configuration is set at the factory at time of manufacture.
Standard is a Normal (Failsafe) action HI/LO configuration where
SP1 is the HI alarm and SP2 is the LO alarm. Gauges with HI/HI,
LO/LO and reverse acting relay configurations are also available.

Normal (Failsafe) vs. Reverse Action - with the Normal or Failsafe
configuration, the alarm output relays will be CLOSED (relay
energized) for a clear or non-alarm condition and OPEN (relay not
energized) for an alarm condition. This is primarily for users who
desire an alarm condition should the gauge lose power. “Normally
closed” and “normally open” designations refer to standard relay
terminology; i.e., the relay contact status with the relay coil not
energized.

With the Normal (Failsafe) configuration, when in a green or non­alarm condition, the relay will be energized so that continuity can be
expected between the common and normally open leads. In a red
or alarm condition, the relay will be open (not energized), so that
continuity can be expected between the common and normally
closed leads.

With the Reverse acting alarm configuration, the relays will be open
(not energized) in the non-alarm condition and closed for the alarm
condition. In this case, continuity can be expected from common to
normally closed in the green (non-alarm) condition and from
common to normally open in the red (alarm) condition. This
configuration can be used if a non-alarm condition is desired when
the gauge power is shut off.

Understanding Deadband - The alarm circuits have built-in
deadbands, also known as hysteresis, of 1% of span as standard.
This means, for example, the deadband is approximately 1 psi in a
0 to 100 psi gauge.

This deadband serves to eliminate output oscillation or “chatter” of
the alarms due to minor fluctuations in pressure. If, for example, the
system pressure in a 0-100 psi system is 40.0 psi, and Setpoint 1 is
set to 50.0 psi (HI alarm), the alarm indication will trip if the
pressure exceeds 50.0 psi. After the HI alar m has tripped, pressing
the SP1 button will show that the alarm indication will “release” at 1
psi lower (approximately 49 psi). Deadband is set at the factory to
1% but other deadbands can be configured at the factory where the
application requires.

Contact Rating and Protection - The contacts of the alarm relays
are rated at 1A/24VDC or 0.5A/115VAC maximum, non-inductive.
Using mechanical relay contacts above their rating, or with large
inductive loads, will shorten their useful life. In circuits other than
low-level switching or pilot duty, the user should consider whether
external contact protection such as snubber networks or arc
suppression networks are required to protect the contacts. When
switching higher electrical loads, the alarm relay should be used to
drive an external contactor or solid state relay of sufficient capacity.

In addition, no internal fusing is included in the gauges. The circuit
external to the gauge alarm outputs should be fused by the user in
applications where good design practice dictates.

Optional Power Supply Kit DPG1000-PS

The optional power supply kit includes a
UL and CSA listed 115 VAC (50/60 Hz)
wall-mount power supply with U.S. style
2-prong plug. Output is 12 VDC at 200
mA and is intended for gauges that
accept DC power. The power supply’s
two-conductor wire is approximately 6
feet long and has plain wire ends. Also
included is a moisture resistant
connector to allow easy hookup without
having to strip wires. Use a pair of pliers
to snap connector onto wires.

1

/4" NPT

2.88"

3.38"

0.75"

1.65"

Turn at

hex

fitting

only!

0.75"

Two 3 ft long, 22
AWG shielded
cables,
2-conductor power,
6 conductor alarm

OMEGA Engineering Inc./Made in USA

TEST

SP1 SP2

PSIG

Zero SP2

Span

Test

SP1