Dwyer Instruments 490A-1 User manual

Series 490A Hydronic Differential Pressure Manometer
Bulletin D-24A
Specifications - Installation & Operating Instructions
SPECIFICATIONS
Service: Compatible gases & liquids.
Wetted Materials: 316 SS; -3V option: 316LSS, Buna-N, silicone, grease, PTFE,
brass 360, copper, reinforced acetal copolymer; - KIT option: 316LSS, PTFE,
brass, copper.
Accuracy: ±0.5% FS from 60 to 78°F (15.6 to 25.6°C); ±1.5% FS from 32 to 60°F
and 78 to 104°F (0 to 15.6°C and 25.6 to 40°C).
Pressure Hysteresis: ±0.1% FS.
Pressure Limits: See chart
Temperature Limits: Operating: 0 to 140°F (-17.8 to 60°C); Process with - KIT
option: -20 to 180°F (-29 to 82°C); Storage: -4 to 176°F (-20 to 80°C).
Display: 4-digit LCD (.425˝ x .234˝ W digits).
esolution: See chart.
Process Connections: Two 1/8˝ (3.18 mm) female NPT; - KIT option: Two 1/4˝
male 45° flare fittings.
Power equirements: 9 V alkaline battery, installed non-functional, user
replaceable.
Weight: 14.1 oz (400 g); - KIT option: 3.6 lb (1.63 kg).
Agency Approvals: CE.
Series 490A Hydronic Differential Pressure Manometer are versatile, hand-held,
battery operated manometers available in several basic ranges for positive or
positive differential pressure measurement and can tolerate most liquid media
compatible with 316LSS. A memory function allows storage of up to 40 readings for
later recall and a backlight provides auxiliary lighting for hard-to-see locations.
Standard are a hold feature and both visual and audible overpressure alarms. A
new feature added to the Series 490A is a field adjustable damping, independent
viewable high/low pressure readings, and low range increased resolution. This
allows the user to choose the level of display averaging rate corresponding to the
fluctuation level common in many applications. A 9 V alkaline battery is included
that provides up to 100 hours of operation.
Model
490A-1
490A-2
490A-3
490A-4
490A-5
490A-6
English
ange
0 to 15 psi
0 to 30 psi
0 to 50 psi
0 to 100 psi
0 to 500 psi
0 to 200 psi
Metric
ange
0 to 103.4 kPa
0 to 206.9 kPa
0 to 344.8 kPa
0 to 689.5 kPa
0 to 3448 kPa
0 to 1379 kPa
Maximum
Pressure
30 psi (2.7 bar)
60 psi (4.13 bar)
100 psi (6.89 bar)
200 psi (13.78 bar)
1000 psi (68.9 bar)
400 psi (27.57 bar)
Available Engineering Units
psi, in w.c., in g, cm w.c., mm g, kPa, hPa, mbar, bar, oz/in2
psi, in w.c., in g, cm w.c., mm g, kPa, hPa, mbar, bar, oz/in2
psi, in w.c., in g, cm w.c., mm g, kPa, hPa, mbar, bar, oz/in2
psi, in w.c., in g, cm w.c., mm g, kPa, hPa, mbar, bar, oz/in2
psi, in w.c., in g, cm w.c., mm g, kPa, hPa, mbar, bar, oz/in2
psi, in w.c., in g, cm w.c., mm g, kPa, hPa, mbar, bar, oz/in2
6-15/64
[158.27]
29/32
[22.86]
2-53/64 [71.73]
1/8 NPT
1-1/4
[31.75]
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BATTE Y INSTALLATION
The unit is shipped with a separate 9 volt alkaline battery which must be installed
before operation. Remove the two screws holding the bottom endcap in place and
remove the endcap. Connect the battery to the enclosed battery clip, making sure
to observe correct polarity. Be careful not to trap wires between the battery, case,
or foam pads which retain the battery. This could make it difficult to install the battery
or remove it later for replacement. Be sure that the rubber gasket is properly seated
in the gasket channel of the endcap and replace endcap. Note that the endcap will
only fit one way because the holes are slightly off-center. Place the Z shaped wrist
strap clip in one of the screw recesses and replace the screws. Do not over tighten
the screws. Attach the wrist strap to the clip. Note: On – KIT option 490A, the
rubber boot will have to be pulled back to have access to the battery compartment.
When battery replacement becomes necessary, use only a 9 volt alkaline type such
as a Duracell®MN 1604, Eveready®522, or equivalent. Zinc-carbon types, often
labeled heavy-duty are not recommended because of the increased potential for
leakage. Alkaline batteries are also a better value because they last up to three
times longer in this device.
Low Battery Indicator
A weak battery can cause improper operation or inaccurate measurements. A low
battery indicator is provided on the display to show when the battery needs
replacement.
ON-OFF OPE ATION
Press the ON/OFF button once to turn the unit on. Once on, press the ON/OFF
button for more than 5 seconds to turn the unit off. If the manometer is left on with
no activity for approximately 20 minutes, the unit will turn itself off to conserve the
battery.
ZE OING P ESSU E EADING
Potential inaccuracy due to temperature effects can be minimized by re-zeroing
immediately before use. To zero the display, vent both ports to the atmosphere so
no pressure is applied to either port. Press the ZERO/STORE button and ---- will
be momentarily displayed as zeroing occurs. Zeroing is not possible when the
memory mode is in use. It must be done before selecting that function.
If the unit is accidentally zeroed with pressure applied to one of the ports, the
pressure reading might display incorrectly. To correct, vent the pressure ports to
atmosphere and press the ZERO/STORE button to zero the unit.
BACKLIGHT
The Model 490A includes a display backlight to allow use in the dark or in poor
lighting conditions. Pressing the ON/OFF button toggles the backlight on or off. With
the 490A on, press the ON/OFF button to toggle the backlight on or off. The
backlight will remain lit for approximately 2 minutes after which it will turn itself off
to conserve battery life.
P ESSU E CONNECTION
Measuring Single Pressure
To measure single positive pressure, connect the tubing to the port marked “ igh
Pressure” and vent the opposite port to the atmosphere.
Measuring Differential Pressure
To measure differential pressure, connect the higher positive pressure to the port
marked “ igh Pressure” and the lower positive pressure to the port marked “Low
Pressure”. The manometer will indicate the difference between the two.
Overpressure Alarm
A visual indicator and audible alarm are provided to alert the user that pressure has
exceeded the operating range of the unit. Exceeding the range will not damage it
or affect calibration as long as the maximum rated pressure is not exceeded. The
maximum pressure for all units is shown on the rear label and on page 1 of these
instructions.
Do not exceed the maximum rated pressure of the manometer.
Doing so will cause permanent damage to the sensor, may
rupture the housing, and/or cause personal injury.
CAUTION
Although the unit might appear to function and indicate properly,
the accuracy of readings cannot be guaranteed when the LOW
BAT indicator is illuminated. Replace the battery with a new one. Do not leave an
exhausted battery in the unit due to potential leakage.
NOTICE
AUTOMATIC ESOLUTION ADJUSTMENT
For all ranges, the series 490A will automatically move the decimal place one point
to the left when reading in the bottom 10% of its calibrated range. This allows the
user to gain a higher resolution reading for lower static or differential pressure
readings.
SELECTING P ESSU E UNITS
Up to seven pressure units are available. The display will indicate the current
selection. To change to different units, use the UNITS/LOC button. Each press of
the button will cause an advance to the next choice. The selected units will remain
in the memory even when the power is shut off. This way, the user preferences will
always be displayed after the initial selection.
DISPLAY HOLD
In situations where a reading needs to be temporarily retained, the Model 490A
includes a display hold feature which freezes the current reading and holds it on
the display until it is cleared. To activate this operation, press the OLD/MEMORY
button when the desired pressure is displayed. A OLD indicator will appear on the
display to indicate that the reading shown is frozen. To return to normal operation,
press the OLD/MEMORY button again. The OLD indicator will disappear and
the current pressure will be shown.
MEMO Y FUNCTION
A memory function is included in the Model 490A that allows users to store up to 40
pressure readings for later review or recording. The readings are stored in non-
volatile memory so they will be retained even if the unit is shut off or the battery is
removed.
Storing Pressure eadings
T
o store a reading, press and hold the OLD/MEMORY button until ST01 displayed.
Next, press the ZERO/STORE button to safe the current reading to the ST01
memory location. A beep will sound indicating that the reading has been saved. As
each reading is saved, the memory location display will advance to the next number.
To resume pressure measurement, press the OLD/MEMORY button again. Note
that in the memory mode, the display zero function is not available. To zero the
display, exit the memory mode and then press the ZERO/STORE button.
Viewing Stored eadings – Selecting a Location
To view the contents of the memory, press and hold the OLD/MEMORY button
until RD01 is displayed. Next, press UNITS/LOC to view other memory locations.
To resume pressure measurement, press the OLD/MEMORY button again.
Clearing Memory
To clear the contents of the memory, press and hold the OLD/MEMORY button
until CLR is displayed. Next, press the ZERO/STORE button to clear all previously
stored readings. During this operation --- will be displayed. Once the memory is
cleared, the current pressure will be displayed.
Exiting Memory Mode
To exit the memory mode, press the OLD/MEMORY button again and the unit will
return to normal operation.
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DAMPENING FUNCTION
The dampening feature allows users to enter a dampening number from 1 to 16
(default value = 2). Entering a larger number increases the amount of readings that
are averaged for each display update.
In order to access the dampening feature:
1. Press and hold the OLD/MEMORY button for 7 seconds until DAMP is
displayed.
2. Once DAMP is selected, a number is shown in the upper right portion of the
LCD, along with the current pressure reading. This number is the dampening
number. Adjust the number up by pressing the ZERO/STORE button or down
by pressing the UNITS/LOC button. The LCD update rate slows as the number
increases from 1 to 16. Therefore, for best results, choose the smallest number
that provides a stable pressure reading.
3. Once the pressure reading is stable, press the OLD/MEMORY button to store
the dampening value.
INDEPENDENT HIGH O LOW STATIC P ESSU E EADINGS
This feature allows the user to select the pressure source to be shown on the LCD.
The selections are LOW (-), IG (+), or DIFF ( IG – LOW) without disconnecting
any process connections.
1. Press and hold the OLD/MEMORY button for 9 seconds until SRCE is
displayed, then release.
2. Next, press the UNITS/LOC button to change the source to the one desired.
3. Press the ZERO/STORE, or ON/OFF or OLD/MEMORY button to store the
source and resume pressure measurement. To return to any other pressure
source reading, please return to step 1. Note: The unit will default to DIFF when
powered on, to return to a differential pressure reading DIFF ( IG -LOW)
simply turn the unit off and then back on.
OPTIONAL 3-WAY VALVE
For certain hydronic applications, it is beneficial to measure the differential pressure
with the assistance of the optional attached 3-way valve. (See Fig. A)
Begin with valve V1 open and valves V2 and V3 closed. (See Fig. B) Slowly open
V2 and V3. Once the pressure has stabilized and is equal on the high and low side,
V1 can be closed and normal operation can proceed. To ensure proper pressures
will be detected by the 490A, use the bleed fitting provided with this valve package.
(See Fig. A) Before applying pressure to the process connections, turn V1 to the
open position and back off the bleed screw. Next apply pressure. After the flowing
liquid is free of bubbles, retighten the bleed screw. Before taking the 490A offline
from the process, open V1 then close V2 and V3.
Figure B
BLEED
FITTING
5-1/4
[133.35] 1-21/64
[33.73]
10-2/5
[264.2]
Figure A
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Duracell® is a registered trademark of The Gillette Company
Everready®is a registered trademark of The Everready Battery Company, Inc.
OPTIONAL HYD ONIC KIT (-HKIT Option)
For hydronic valve balancing, Dwyer offers a full comprehensive kit of components
to be able read pressure across valves by tapping the pressure test ports on either
side of the valve or pump. The kit is comprised of two sets of 60˝ hoses with integral
ball valves, 3 pairs of various size gage piercing adapters, adapters for various
installations and a 3 way valve. The 3 way valve allows for isolation of pressure,
equalization between high /low and bleeding of lines to evacuate air or particulate.
(See Fig. C). Please use following procedure as a guide when reading differential
pressure across a hydronic valve or pump.
1. Begin with valve V1 open and valves V2 and V3 closed. (See Fig. D) Verify the
integral ball valves on the red and blue hoses are in the open position. Then
slowly open valves V2 and V3.
2. Once the pressure has stabilized and is equal on the high and low side, valve
V1 can be closed and normal operation can proceed.
3. To ensure proper pressures will be detected by the 490A, use the bleed fittings
for the high & low pressure sources on either side of the 3-valve manifold
assembly. (See Figure D) These can be adjusted with the use of the adjustable
wrench in the kit. PVC tubing has also been provided for connection to the bleed
fitting giving the ability to control the bleeding into a container or reservoir. Once
the lines are clear of pockets of air, close each bleed fitting with the wrench
provided.
4. With valve V1 closed, bleed fittings tightened, valves V2 and V3 open, take the
necessary readings.
5. Once the readings are completed, it is best practice to close off the integral ball
valves in the red and blue hoses and leave valves V2 and V3 open. Then using
the bleed fittings once more, loosen and bleed out the pressurized fluid or gases.
The PVC tubing can be used once more to control the bleeding of the fluid into
a container or reservoir.
6. Maintaining the integral hose ball valves in the closed position, disconnect from
the pressure test ports.
Figure C
Figure D
7-5/64 [179.78]
11-55/64
[301.23]
3-5/32
[80.17]
3-5/32
[80.17]
LOW PRESSURE
BLEED FITTING
HIGH
PRESSURE
BLEED
FITTING
2-21/32
[67.47]
2X Ø5/16
[Ø7.94]
LOW PRESSURE
BLEED FITTING
V1
HIGH PRESSURE
BLEED FITTING
V2 V3
MAINTENANCE/ EPAI
Upon final installation of the Series 490A, no routine maintenance is required. The
Series 490A is not field serviceable and should be returned if repair is needed. Field
repair should not be attempted and may void warranty.
WA ANTY/ ETU N
Refer to “Terms and Conditions of Sale” in our catalog and on our website. Contact
customer service to receive a Return Goods Authorization Number before shipping
the product back for repair. Be sure to include a brief description of the problem
plus any additional application notes.
Model
A-HKIT-AFIT
A-HKIT-BFIT
A-HKIT-HOSES
A-HKIT-500
A-HKIT-500XL
A-HKIT-510
UHH-ST AP
A-47X-BOOT
A-203
Description
Adapter fitting replacement kit including:
Straight adapter, 1/4˝ Male NPT X 1/4˝ - 45° flare (2 per kit)
1/4˝ SAE 45° flare seal cap and gasket (2 per kit)
90° union elbow, 1/4˝ - 45° flare X 1/4˝ - 45° flare (2 per kit)
90° male elbow, 1/4˝ male NPT X 1/4˝ - 45° flare (2 per kit)
Bleed fitting assembly (2 per kit)
60˝ blue charging hose with valve
60˝ red charging hose with valve
Piercing gauge adapter 1/8˝ DIA x 1-1/2˝ Length (2 per kit)
Piercing gauge adapter 1/8˝ DIA x 3˝ Length (2 per kit)
Piercing gauge adapter 1/16˝ x 1-1/2˝ Length (2 per kit)
Pipe or carry strap
Rubber boot
PVC tubing 1/4˝ OD x 1/8˝ ID. Ordered per foot
490-X-HKIT Field eplacement Parts
Please call our customer service for pricing and availability at 219-879-8000 or
email: [email protected]
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