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490 Low Pressure Diaphragm Gauge
1
• Glass-filled polysulfone case material,
won’t rust or dent
• Beryllium copper diaphragm
• Brass socket
• Wetted materials of beryllium copper,
brass, polysulfone and RTV silicone
The Ashcroft® Type 1490 low pressure
diaphragm gauge is designed to measure
pressure from 10 in. H
positive and negative pressures. This
gauge uses a very sensitive diaphragm
capsule to measure low pressure and
vacuum. The gauge is specific ally
designed for use whenever the pressure
medium is a gas that is not corrosive to
beryllium copper, brass, polysulfone and
RTV silicone. The polysulfone case is
suitable for intermittent or continuous
service on natural gas provided a .013
throttle plug is installed in the socket.
Typical applications are, but not limited
to, vacuum pumps, gas leak detectors, air
compressors, air filters, gas burners, gas
measurement, vacuum ovens, suction
regulators and respirators.
O to 15 psi, both
2
PRODUCT SPECIFICATIONS
Model Number: 1490
Accuracy: ±2-1-2% full scale
(Grade A, ASME B40.100)
Ranges: 10 in. H2O through 15 psi
including vac. and compound
Dial Size: 21⁄
Case Material:
Black, glass filled polysulfone
2˝ and 3
1
⁄
2˝ diameter
Socket Material: Brass
Movement:
Brass
Sensing Element: Beryllium copper diaphragm
Wetted Material: Beryllium copper, brass,
polysulfone and RTV silicone
Window: Polycarbonate, quarter turn
bayonet style mounting
Dial: Aluminum, white background,
black figures and intervals.
Pointer: Black, aluminum, fixed
Connection
Size:
1
⁄
8 NPT (01)
1
⁄
4 NPT (02)
1
⁄
8˝ tubing hose barb (HD)
3
⁄
16˝ tubing hose barb (HE)
1
⁄
4˝ tubing hose barb (HF)
1
⁄
4˝ O.D. polytube hose barb (HG)
10-32 2B female thread (HH)
Connection
Location: Lower (L)
Center Back (B)
Top (T)
3 o’clock (D)
9 o’clock (E)
Operating
Temperature: –40 to 180°F
Proof Pressure: 150% of range
Burst Pressure: Up to 5 psi = 50 psi
Greater than 5 psi = 100 psi
OPTIONAL FEATURES
1% Accuracy:
XAN
Dial Marking: XDA
Stainless
Steel Tag:
XNH
Paper Tag: XNN
Throttle Plug:
Throttle Screw:
U-clamp:
(1)(3)
XTU
(4)
XTS
(2)
XUC
FlutterGuard™: XZY
(1) A throttle plug must be installed in the socket whenever
the gauge is used for intermittent or continuous service
on natural gas.
(2) U-clamp furnished when hose barb or female thread is
specified.
(3) Throttle plug not available with hose barb or female thread
connections.
(4) .020 throttle screw available with HH connection only.
BULLETIN DG-1490
All specifications are subject to change without notice.
All sales subject to standard terms and conditions.
© Ashcroft Inc. 2018 07/18
Ashcroft Inc., 250 East Main Street, Stratford, CT 06614 USA
Tel: 203-378-8281 • Fax: 203-385-0408
email: info@ashcroft.com • www.ashcroft.com
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490 Low Pressure Diaphragm Gauge
1
STANDARD RANGES
Pressure Figure Intervals Minor Graduation
0/10 in.H2O 1 0.1
0/15 in.H2O 5 0.2
0/30 in.H2O 5 0.5
0/60 in.H2O 10 1
0/100 in.H2O 10 1
0/160 in.H2O 20 2
0/200 in.H2O 20 2
0/300 in.H2O 50 5
2
0/10 oz./in.
0/15 oz./in.
2
1 0.1
5 0.2
0/30 oz./in.2 5 0.5
0/60 oz./in.2 10 1
0/100 oz./in.2 10 1
0/160 oz./in.2 20 2
0/250 oz./in.2 50 5
0/3 psi 0.5 0.05
0/5 psi 1 0.1
0/10 psi 1 0.1
0/15 psi 5 0.2
STANDARD RANGES (Cont.)
Vacuum Figure Intervals Minor Graduation
15/0 in.H2O 5 0.2
30/0 in.H2O 5 0.5
60/0 in.H2O 10 1
100/0 in.H2O 10 1
200/0 in.H2O 20 2
15/0 oz./in.
2
5 0.2
30/0 oz./in.2 5 0.5
60/0 oz./in.2 10 1
100/0 oz./in.2 10 1
Compound
–30/30 in.H2O 10 1
–30/30 in.oz./in.
2
10 1
–10/10 in.H2O 2 0.2
Dual Scale
Graduations
Range
Inner Scale Outer Scale
0/9 oz./in.2 0/15 in.H2O 1 0.2 5 0.2
2
0/20 oz./in.
0/35 oz./in.
0/60oz./in.2 0/100 in.H2O 10 1 10 1
0/35 in.H2O 5 0.5 5 0.5
2
0/60 in.H2O 5 0.5 10 1
Inner Scale Outer Scale
Figure Minor Figure Minor
Intervals Grad. Intervals Grad.
STANDARD METRIC RANGES
Pressure Figure Intervals Minor Graduation
0/60 cm. H2O 10 1
0/2.5 kPa 0.5 0.05
0/4 kPa 1 0.1
0/10 kPa 1 0.1
0/16 kPa 2 0.2
0/25 kPa 5 0.5
0/40 kPa 10 1
0/100 kPa 10 1
Vacuum
2.5/0 kPa 0.5 0.05
4/0 kPa 1 0.1
10/0 kPa 1 0.1
16/0 kPa 2 0.2
25/0 kPa 5 0.5
40/0 kPa 10 1
100/0 kPa 10 1
Compound
–10/60 cm H2O 10 1
–10/80 cm H2O 10 1
–20/40 cm H2O 10 1
–10/100 cm H2O 10 1
–10/120 cm H2O 20 2
Other ranges available on request. Consult factory.
SELECTION TABLE
Dial Size Type Wetted Material Conn. Size & Type Connection Location Ranges Optional Features
Code Desc. Code Description Code Description Code Description Code Description Code Description Code Description
1
25 2
/2˝
Low Pressure A Beryllium Copper 01
35 31/2˝ Diaphragm Gauge Brass 02
1490
Polysulfone HD 1/8˝ I.D.Tubing Hose Barb
RTV Silicone HE 3/16˝ I.D.Tubing Hose Barb
HF 1/4˝ I.D.Tubing Hose Barb
HG 1/4˝ O.D. Polytube Hose Barb
HH 10-32-2B Female Thread
1
/8 NPT L Lower 10 IW 0 to 10 in.H2O XAN 1% Opt. Accuracy
1
/4 NPT B Center Back XDA Dial Marking
(2,3)
T Top See Chart for XNH Stain. Steel Tag
(2,3)
D 3 O’Clock Entire List of XNN Paper Tag
(2,3)
E 9 O’Clock Ranges XTU
(2,3)
XTS
(2,3,5)
XUC
(1,3)
Throttle Plug
(4)
Throttle Screw
(2)
U-clamp
XZY FlutterGuard™
(1) A throttle plug must be installed in the socket whenever the gauge is used for intermittent or continuous service on natural gas.
(2) U-clamp furnished when hose barb or female thread is specified.
(3) Throttle plug not available with hose barb or female thread connections.
(4) .020 throttle screw available with HH connection only.
BULLETIN DG-1490
HOW TO ORDER: 25 1490 A 02L XXX 10 IW
1. Dial size – 21⁄2 (25), 31⁄2 (35)
2. Case type
3. Wetted material
4. Connection size – 1⁄4 (02), 1⁄8 (01)
5. Connection location – Lower (L), Back (B)
6. Optional features
7. Standard pressure range – 10 in.H2O
All specifications are subject to change without notice.
All sales subject to standard terms and conditions.
© Ashcroft Inc. 2018 07/18
Ashcroft Inc., 250 East Main Street, Stratford, CT 06614 USA
Tel: 203-378-8281 • Fax: 203-385-0408
email: info@ashcroft.com • www.ashcroft.com