Starting at $544.00

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  • Humidity measurement range: 0 to 100% RH
  • Temperature measuring ranges:
    • HM41; 14 to 140°F (-10 to 60°C)
    • HM42; -40 to 212°F (-40 to 100°C)
    • HM45; -40 to 140°F (-40 to 60°C)
    • HM46; -40 to 212°F (-40 to 100°C)
  • Cable lengths:
    • HM41; no cable
    • HM42/HM46; 1.5m
    • HM45; 1.2m
  • Vaisala HUMICAP sensor technology
  • Large graphic display
  • Displays a wide range of quantities: RH, T, Td, Tw, a, x, h
  • Compact and robust housing
  • Hold-button to freeze the screen
  • Multilingual user interface with 10 languages

What's in the Box

  • Humidity / temperature probe plus indicator
  • Calibration certificate
  • Light carrying case
  • Alkaline batteries 2x AA sized
  • User's guide

The Vaisala HM40 Series Humidity and Temperature Meters are compact and portable humidity meter that provides reliable measurements in a wide range of applications. It is the ideal spot-checking tool for everything from structural moisture measurement and air conditioning systems to humidity measurement in industrial production processes and life science applications. There are four different models available: HM41, HM42, HM45, and HM46.

The HM40 has a large, user-friendly graphical display and easy-to-use push buttons. The user interface is simple and intuitive, and available in 10 languages. Also, many settings can be modified to meet users' individual needs. In addition to relative humidity and temperature, the HM40 provides five calculated humidity parameters, all of which are available in metric and non-metric units.

The HM40 is powered by 2 AA batteries. An external NiMH charger with USB connection and rechargeable AA sized NiMH batteries are available as an option. Each model also comes with a handy belt clip and case.