Detail Elcometer 309 Digital Delta T Hygrometer
Digital Delta T Hygrometer | Elcometer 309
Before painting, the coater must meet the coatings’ parameters. These are clearly specified on the paint manufacturer’s product data sheet.
Relative Humidity (RH) and Delta T (TΔ) are the two climatic values which are specified on data sheets.
The Elcometer 309 Delta T Hygrometer provides a simple and fast measurement of these two critical characteristics.
- Delta T (TΔ): The difference between the surface temperature (Ts) and the dewpoint temperature (Td). When TΔ is less than 3ºC (5ºF) painting should not occur.
- Relative Humidity (RH): This is the amount of water vapour taken up by air. Expressed as a percentage, RH is dependent on the air temperature. Typical maximum RH values specified by paint manufacturers are between 75% and 85%.
Rugged design: Suitable for use in extreme environments the Elcometer 309 digital hygrometer is dustproof and waterproof with fully sealed sensors.
High / Low Limits: Displayed on screen graphically as either (?) or (X) with flashing Red or Green LED’s to indicate pass or fail.
Delta T Temperature: TΔ is pre-set at >3ºC (>5ºF), the industry norm.
Relative Humidity: User definable upper limit can be set for RH.
Measurement Hold / Release function: With a single button press readings are ‘frozen’ on the screen. These can then be recorded before, simply pressing the button again to ‘unfreeze’ the screen and then take further readings as necessary.
Backlight: Provides clearly lit information – ideal in dark or confined spaces.
For more information on Hygrometers, read our Hygrometer information page.
Technical Specifications – Elcometer 309 Delta T Hygrometer
23°F to 122°F (-5°C to 50°C)
Temperature Range (Air & Surface)
-4 to +176°F (-20 to +80°C)
Relative Humidity (RH) Range
0 to 100%RH (Default upper limit 75%, user adjustable)
0.1°C / 0.1%
2 x AA 1.5V Batteries or via USB Cable
Greater than 40 hours (Backlight off)
7 x 3 x 1.4″ (180 x 75 x 35mm)
Certificate of Calibration: issued for Fixed Calibration equipment and shows readings and traceability
- Elcometer 309 Delta T Hygrometer
- wrist strap
- 2 x AA batteries
- protective pouch with belt clip
- RH probe calibration certificate
- operating instructions