Model-475-1T

Supported Applications

The Series 475-AV Air Velocity Kits pair a Series 475 Mark III digital manometer with a pitot tube and tips to balance system air flows. The kits are small, light and easy to use with no setup or leveling needed, which makes them well suited to plant engineers and HVAC technicians working in the field.

Typical uses include building commissioning, HVAC test and balance, critical environment testing, industrial process verification and instrumentation validation. The manometer measures air and compatible gases, and air velocity is derived from the pressure the pitot tube senses in the duct. Because the pitot tip has very small sensing holes, the airflow must be reasonably clean and free from particulates that could cause blockage.

Operating Conditions & Performance

The digital manometer provides an accuracy of ±0.5% FS and a resolution of 0.01, with hysteresis of ±0.1% of full scale. The reference accuracy is specified over 15.6 to 25.6°C, and the instrument is powered by a 9 V battery with a low-battery warning.

The T-designated kits in this range cover pressure ranges from 0-4.000 in w.c. up to 0-20.00 in w.c. The Series 475 manometer has a large 1/2" LCD readout, while the related Series 477AV manometer adds a backlit 0.4" LCD with both audible and visual overpressure alarms. The manometer body is polyethylene and the pitot tube is stainless steel.

Each kit is supplied in a fitted polyethylene carrying case and includes a Model 166-6-CF 6" stainless-steel pitot tube with integral compression fitting, or a Model 166T 36" telescoping stainless-steel pitot tube fully adjustable from 11.5" to 36" (29.2 to 91.4 cm). Also packed in are two No. A-303 static pressure tips with magnetic mounting, 3/16" I.D. rubber tubing, a No. A-397 step drill and a No. A-532 air velocity slide chart.

Configuration Options

Within the telescoping-tube (T) kit family the variants differ almost entirely by the manometer pressure range, which sets the span of air velocity that can be balanced:

• 475-00T-FM-AV — 0-4.000 in w.c. range for low-pressure work.
• 475-0T-FM-AV — 0-10.00 in w.c. range for mid-range duct pressures.
• 475-1T-FM-AV — 0-20.00 in w.c. range for higher duct pressures.

All three share the same ±0.5% FS accuracy, 0.01 resolution, 9 V battery, stainless-steel telescoping pitot tube and fitted case, so the range chosen simply matches the duct pressures expected on site.

Key Product Differences

The Series 475 air velocity kits are ordered by range code, with the telescoping-tube variants being:

• 475-00T-FM-AV — 0-4.000 in w.c.
• 475-0T-FM-AV — 0-10.00 in w.c.
• 475-1T-FM-AV — 0-20.00 in w.c.

These follow the 475-XXT-FM-AV model scheme; companion 475-XX-FM-AV kits and the four-model 477AV-XXXT-AV kits cover the same in-w.c. ranges with different manometer and tube options.