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Red handheld hot-wire anemometer with infrared thermometer

Sentry

Sentry ST-733 hot-wire anemometer electrician tool

SKU CH-CYP9-1P7XC MPN ST-733

Measures air velocity and ambient temperature simultaneously with a hot-wire sensor, plus infrared surface readings to 537 °C at 30:1 distance-to-spot ratio

  • Color/FinishRed
  • Item Count1 pack
  • Selling UnitBox
  • Parts3 Years
  • Labor1 Year
  • Simultaneous air velocity and temperature read-outs
  • Hot-wire sensor delivers precise low-velocity measurements
  • Infrared thermometer reaches 537 °C with 30:1 spot ratio
  • Multiple units: m/s, km/h, ft/min, knots, mph, CMM, CFM
  • Auto power-off after 10 minutes idle, 30 with AC power

Purpose and User

The Sentry ST-733 is a hot-wire anemometer designed for electricians and ventilation specialists who need simultaneous air-velocity and temperature readings in a single handheld instrument. It suits professionals balancing HVAC ducts, commissioning exhaust systems or troubleshooting airflow in electrical enclosures. Buyers who require data logging or wireless connectivity will not find those functions here.

Deciding Specification

The 30:1 distance-to-spot ratio on the built-in infrared thermometer lets you measure surface temperatures up to 537 °C (999.5 °F) from a safer distance than the 8:1 ratio found on the 730 and 732 models. This single optical spec determines whether the tool can reach the targets you face without climbing or shutting down equipment.

Build Integration

The meter runs on battery power and will auto power off after 10 minutes of idle time, extending field use between charges; an AC adapter changes that timeout to 30 minutes for bench work. It delivers velocity in m/s, km/h, ft/min, knots and mile/h plus volumetric flow in CMM and CFM, so you can match the units your schematics specify without carrying a conversion chart.

Highlights

  • Simultaneous air velocity and temperature read-outs
  • Hot-wire sensor delivers precise low-velocity measurements
  • Infrared thermometer reaches 537 °C with 30:1 spot ratio
  • Multiple units: m/s, km/h, ft/min, knots, mph, CMM, CFM
  • Auto power-off after 10 minutes idle, 30 with AC power

Specifications

BrandSENTRY
ModelST-733
Color/FinishRed
Item Count1 pack
Selling UnitBox
Parts3 Years
Labor1 Year

Questions about this item

What does the 537 °C infrared limit mean when I am checking duct surfaces?

The built-in infrared thermometer can read surface temperatures up to 537 °C from a distance, using a 30:1 spot ratio so you can measure hot registers or motors without contact.

How does the 30:1 distance-to-spot ratio affect the size of the area I am measuring?

At 30 cm away the instrument reads a 1 cm circle, letting you target a single diffuser or motor housing without averaging surrounding surfaces.

What mounting or power provisions does the ST-733 need for extended logging sessions?

The meter runs on batteries and auto-powers off after 10 minutes idle; connect the optional AC adapter to extend the timeout to 30 minutes for longer tests.

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