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Series 490A Hydronic Differential Pressure Manometer

Series 490A Hydronic Differential Pressure Manometer

Series 477AV Handheld Digital Manometer

Series 477AV Handheld Digital Manometer

Series 477B Handheld Digital Manometer

Precise Air Pressure Measurement, ±0.1% F.S. Accuracy

The Series 477B Handheld Digital Manometers are versatile, hand-held, battery operated manometers available in several basic ranges from 0-20 in w.c. up to 100 psi. All models measure either positive, negative or differential pressures with ±0.10% of full scale accuracy. You can select from up to seven common English and metric pressure units so conversions are not necessary. A memory function allows storage of up to 40 readings for later recall and a backlight provides auxiliary lighting for hard-to-see locations. Also standard are a hold feature plus both visual and audible overpressure alarms.

NIST CALIBRATION available in Product Configurator.

Product Applications

  • Lab calibration of other pressure instruments
  • Air velocity/air flow measurements in commercial buildings
Starting at $489.00
Grouped product items
Model Description Availability* Qty Price
477B-1 Handheld digital manometer, 0 to 20" w.c. (0 to 4.982 kPa) 1-3 days*
477B-2 Handheld digital manometer, 0 to 40" w.c. (0 to 9.96 kPa) 1-3 days*
477B-3 Handheld digital manometer, 0 to 200" w.c. (0 to 49.82 kPa) 2-3 Weeks*
477B-4 Handheld digital manometer, 0 to 10 psi (0 to 68.95 kPa) 2-3 Weeks*
477B-5 Handheld digital manometer, 0 to 30 psi (0 to 206.9 kPa) 2-3 Weeks*
477B-6 Handheld digital manometer, 0 to 50 psi (0 to 344.7 kPa) 2-3 Weeks*
477B-7 Handheld digital manometer, 0 to 100 psi (0 to 689.5 kPa) 2-3 Weeks*


Air and compatible gases.
Wetted Parts:
Consult factory.
±0.10% of full scale from 60 to 78F° (15.6 to 25.6°C); ±1% of full scale from 32 to 60 and 78 to 104°F (0 to 15 .6 and 25.6 to 40°C).
Pressure Hysteresis:
±0.1% of full scale.
Pressure Limits:
See chart on catalog page.
Temperature Limits:
0 to 140°F (-17.8 to 60°C).
Storage Temperature Limits:
-4 to 176°F (-20 to 80°C).
4-digit LCD (.425" H x .234" W digits).
See chart on catalog page.
Power Requirements:
9 volt alkaline battery, included but not connected.
Two barbed connections for use with 1/8" (3.18 mm) or 3/16" (4.76 mm) I.D. tubing for 477B-1, 477B-2, 477B-3, 477B-4 and 477B-5 only. Two compression fittings for use with 1/8" (3.18 mm) I.D. x 1/4" (6.35 mm) O.D. tubing for 477B-6 and 477B-7 only.
10.2 oz. (289 g).
Agency Approvals:


  • Precise 0.1% FS accuracy provides four times better accuracy than most standard manometer/gages
  • Aluminum housing protects instrument against damage
  • 40 readings in internal memory reduces time to record data

Product Literature


Catalog Pages


Model Chart

EXAMPLE 477B 1 AT Series 477B-1-NIST Handheld Digital Manometer, range 0-20.00" w.c., with NIST calibration.
SERIES 477B     Handheld Digital Manometer
  0-20.00" w.c.
0-40.00" w.c.
0-200.0" w.c.
0-10.00 psi
0-30.00 psi
0-50.00 psi
0-100.0 psi

Certificate of Calibration
Factory Calibration Certificate
NIST Certificate of Calibration
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Model Description Availability* Price
A-402A Carrying case for most manometers; tough, gray nylon pouch, double zippered with belt loop 1-3 days*
A-47X-BOOT Rubber boot for manometers (manometer not included) 1-3 days*