Dwyer Magnehelic Manual Del Usuario

The Magnehelic ® Differential Pressure Gage consists
of two pressure-tight compartments separated by a
molded flexible diaphragm.
The interior of the gage case serves as the "high"
pressure compartment and a sealed chamber
behind the diaphragm serves as the "low" pressure
compartment.
Differences in pressure between the "high" and
"low" sides of the diaphragm cause the diaphragm
to assume a balanced position between the two
pressures. The front support plate of the diaphragm
is linked to a leaf spring which is anchored at one
end. The spring provides calibrated resistance to the
diaphragm motion. Motion of the spring is
transmitted through an exclusive magnetic linkage
to the pointer.
The Magnehelic ® Differential Pressure Gage requires
no maintenance. The only field adjustment required
is occasional zero setting of the pointer which is
done by opening the plastic vent valves and turning
the adjustment of the gage.
STANDARD GAGE ACCESSORIES: Two 1/8˝ NPT
plugs for duplicate pressure taps, two 1/8˝ pipe
thread to rubber tubing adapters and three flush
mounting adapters with screws.
MP AND HP GAGE ACCESSORIES: Mounting ring
and snap ring retainer substituted for 3 adaptors,
1/4" compression fittings replace 1/8" pipe thread to
rubber tubing adaptors.
DWYER INSTRUMENTS, INC.
P.O. BOX 373 • MICHIGAN CITY, INDIANA 46361 U.S.A.
Magnehelic
(3) 6-32 X 3/16 (4.76) DEEP
HOLES EQUALLY SPACED ON A Ø4-1/8
* RUBBER PRESSURE RELIEF (104.78) BOLT CIRCLE FOR PANEL MOUNTING
PLUG WILL UNSEAT ITSELF WHEN
GAGE IS OVERPRESSURIZED
11/16
(17.46)
11/16
(17.46)
® Differential Pressure Gage
1/8 FEMALE NPT
HIGH PRESSURE
CONNECTION
1-1/4
1-3/4
(31.75)
(44.45)
Ø4-1/2
(114.3)
1/2
(12.70)
1/8 FEMALE NPT
15/32
LOW PRESSURE
(11.91)
CONNECTION
1-11/16
(42.86)
1/8 FEMALE NPT
HIGH PRESSURE
CONNECTION
1-1/4
1-3/4
(31.75)
(44.45)
ø4-1/2
(114.3)
1/2
(12.70)
1/8 FEMALE NPT
LOW PRESSURE
CONNECTION
15/32
(11.91)
*The blowout plug is not used on models above 180
inches of water pressure, medium or high pressure
models, or on gages which require an elastomer
other than silicone for the diaphragm.
SPECIFICATIONS
Service: Air and non-combustible, compatible
gases. (Natural Gas option available.)
Wetted Materials: Consult factory.
Housing: Die cast aluminum case and bezel, with
acrylic cover. (MP model has polycarbonate cover).
Accuracy: ±2% of full scale (±3% on - 0, -100 Pa, -
125 Pa, 10MM and ±4% on -00, - 00N, -60 Pa, -
6MM ranges), throughout range at 70°F (21.1°C).
Pressure Limits: -20˝ Hg to 15 psig.† (-0.677 bar
to 1.034 bar); MP option: 35 psig (2.41 bar), HP
option: 80 psig (5.52 bar).
Overpressure: Relief plug opens at approximately
25 psig (1.72 bar), standard gages only. The
blowout plug is not used on models above 180
inches of water pressure, medium or high pressure
models, or on gages which require an elastomer
other than silicone for the diaphragm.
Temperature Limits: 20 to 140°F (-6.67 to 60°C).
*Low temperature models available as special option.
Size: 4˝ (101.6 mm) diameter dial face.
Mounting Orientation: Diaphragm in vertical
position. Consult factory for other position
orientations.
Process Connections: 1/8˝ female NPT duplicate
high and low pressure taps - one pair side and one
pair back.
Weight: 1 lb 2 oz (510 g), MP & HP 2 lb 2 oz (963 g).
†For applications with high cycle rate within gage total pressure rating,
next higher rating is recommended. See Medium and High pressure
options.
Note: May be used with hydrogen when ordering Buna-N
diaphragm. Pressure must be less than 35 psi.
Phone: 219/879-8000
Fax: 219/872-9057
Lit-by-Fax: 888/891-4963
Bulletin A-27
.025 (.64) SPACE CREATED BY 3 SPACER
PADS WHEN SURFACE MOUNTED.
DO NOT OBSTRUCT. PROVIDES PATH FOR
RELEIF OF OVERPRESSURE.
17/32
(13.49)
1/8 FEMALE NPT
HIGH PRESSURE
CONNECTION
1/8 FEMALE NPT
LOW PRESSURE
CONNECTION
7/16
(11.11)
ø4-3/4 (120.65) PANEL CUTOUT
17/32
(13.49)
ø5
(127)
ø4-47/64
(120.27)
2-17/32 3/16
(64.29) (4.76)
www.dwyer-inst.com
e-mail: info@dwyer-inst.com
Ø4-3/4
(120.65)
ø5-1/2
(139.70) MOUNTING RING