Series-477AV

Supported Applications

The Dwyer Series 477AV is a handheld digital manometer designed for pressure, flow, and air velocity measurements. The instrument utilizes a differential pressure sensor to display negative, positive, and differential pressure values. It includes built-in calculations for volumetric flow and air velocity, supporting applications such as HVAC duct traverses with Pitot tubes, airflow monitoring, commercial air balancing, and building-zone pressure checks.

Documented use cases include:

• Airflow monitoring
• Duct static pressure measurement
• Pitot tube traverses for HVAC technicians
• Instrumentation verification by maintenance personnel

Operating Conditions & Performance

The Series 477AV operates within an ambient temperature range of 0 to 140°F (-17.8 to 60°C). Accuracy is specified as ±0.5% FS at temperatures between 60 to 78°F (15.6 to 25.6°C) and ±1.5% FS from 32 to 60°F and 78 to 104°F (0 to 15.6°C and 25.6 to 40.0°C). Pressure hysteresis is rated at ±0.1% FS.

Measurement ranges span from low differential pressures up to high static pressures, with specific models covering:

• Pressure: 0 to 1 in w.c., 0 to 4 in w.c., 0 to 10.0 in w.c., 0 to 20.0 in w.c., 0 to 40.0 in w.c., and 0 to 200.0 in w.c.
• Pressure: 0 to 10.0 psi, 0 to 20.0 psi, 0 to 30.0 psi, 0 to 100.0 psi, and 0 to 150.0 psi.

The instrument is rated for service with air and compatible gases. Storage temperature limits are -4 to 176°F (-20 to 80°C). The device features a 0.42" (10.6 mm) 4-digit LCD display with backlighting.

Configuration Options

The series offers configurable pressure ranges, selectable engineering units for pressure, velocity, and flow, and data logging capabilities. Key configuration options include:

• Process Connections: Two barbed connections compatible with 1/8" (3.18 mm) or 3/16" (4.76 mm) ID tubing are standard on most models. Models 477AV-7 and 477AV-8 include two compression fittings for use with 1/8" (3.18 mm) ID x 1/4" (6.35 mm) OD tubing.
• Measurement Modes: Selectable modes for Pressure, Velocity, or Volumetric Flow. Units of pressure include in w.c., ft w.c., in Hg, psi, oz/in², mm w.c., cm w.c., mm Hg, mbar, Pa, kPa, and hPa.
• Velocity & Flow: Velocity units available are fpm, fps, mph, m/h, m/s, k/h, and knot. Flow units include cfm, m³/h, and m³/s.
• Data Management: The instrument can store up to 40 readings in memory, which remain saved even when powered off. Features include min/max statistics averaging (AVG), log review (LOG), and the ability to erase individual or all stored readings via menu navigation.
• Housing & Power: Constructed with a rugged aluminum case, weighing 10.2 oz (289 g). Powered by a user-replaceable 9 V alkaline battery (installed non-functional).

Additional features accessible via the advanced menu include digital dampening (adjustable from 1 to 9), audible alarms for over/under pressure or flow, auto power-off settings (configurable from 1 to 20 minutes or disabled), and field calibration of zero and span values.

Available Options & Accessories

• -AV: Air velocity kit
• -COC: Certificate of calibration
• -FC: Factory calibration
• -NIST: NIST traceable calibration certificate
• A-47X-BOOT: Protective magnetic rubber boot
• A-402A: Carrying case (tough gray nylon pouch, 7-1/2"H x 3"W x 2-1/4"D)

Key Product Differences

The Series 477AV is differentiated by model suffixes that correspond to specific pressure ranges and maximum overpressure limits. The standard ordering format follows the pattern 477AV-<Range Code>. For example, models range from 477AV-000 (0 to 1 in w.c.) through 477AV-8 (0 to 150.0 psi).

Specific model distinctions include:

• Low Range Models (in w.c.): Models -000, -00, -0, -1, -2, and -3 cover ranges from 0 to 1 in w.c. up to 0 to 200.0 in w.c., with maximum pressures ranging from 5 psig to 30 psig.
• High Range Models (psi): Models -4, -5, -6, -7, and -8 cover ranges from 0 to 10.0 psi up to 0 to 150.0 psi, with maximum pressures ranging from 30 psig to 200 psig.
• Connection Variants: Only models 477AV-7 and 477AV-8 are equipped with compression fittings; all other standard variants utilize barbed connections only.