Series-477B

Supported Applications

The Dwyer Series 477B Handheld Digital Manometer is designed for measuring positive, negative, or differential air pressure. The series supports applications involving air and compatible gases across a range of basic scales from 0 to 20 in w.c. up to 100 psi.

Operating Conditions & Performance

The Series 477B operates within an ambient temperature range of 0 to 140°F (-17.8 to 60°C) and can be stored between -4 to 176°F (-20 to 80°C). Accuracy is specified as ±0.1% F.S. from 60 to 78°F (15.6 to 25.6°C), with performance of ±1% F.S. from 32 to 60 and 78 to 104°F (0 to 15.6 and 25.6 to 40°C). Pressure hysteresis is rated at ±0.1% F.S.

Each model features a maximum pressure limit defined by its range:

• Models 477B-1 & 477B-2 (in w.c.): Maximum Pressure of 3 psi (0.21 bar)
• Model 477B-3 (in w.c.): Maximum Pressure of 15 psi (1.03 bar)
• Models 477B-4, 477B-5: Maximum Pressures of 30 psi and 60 psi respectively
• Models 477B-6 & 477B-7 (psi): Maximum Pressures of 100 psi and 200 psi respectively

The unit includes visual and audible overpressure alarms to indicate when the maximum rated pressure is exceeded.

Configuration Options

The series offers seven distinct models (477B-1 through 477B-7) covering different measurement ranges. Process connections vary by model:

• Models 477B-1 to 477B-5: Equipped with two barbed connections for use with 1/8" (3.18 mm) or 3/16" (4.76 mm) I.D. tubing.
• Models 477B-6 and 477B-7: Equipped with two compression fittings for use with 1/8" (3.18 mm) I.D. x 1/4" (6.35 mm) O.D. tubing.

All models feature a 4-digit LCD display, a backlight for low-light conditions, and a memory function capable of storing up to 40 readings. Users can select from multiple pressure units including psi, in w.c., in Hg, mm w.c., mm Hg, Pa, kPa, bar, mbar, ft w.c., depending on the specific model range.

Power is supplied by a user-replaceable 9 V alkaline battery (included but not connected). The housing material is aluminum. Wetted materials require consultation with the factory.

Key Product Differences

The primary distinction between models in the Series 477B is the measurement range and corresponding maximum pressure rating, which dictates the process connection type (barbed vs. compression). The series supports an optional NIST traceable calibration certificate by adding the suffix "-NIST" to the model number.

Available accessories include:

• A-402A: Carrying case; tough gray nylon pouch with double zipper and belt loop (7-1/2"H x 3"W x 2-1/4"D).
• A-47X-BOOT: Protective magnetic rubber boot.