Moisture and Relative Humidity Meter - MRH3

Moisture Meter For Measuring And Evaluating Moisture Content And Relative Humidity In Building Materials



The Tramex MRH3 is a non-destructive moisture meter for measuring & evaluating moisture content instantly in building materials such as wood, plaster, drywall, brick, roofing. The MRH3 features a plug in port for optional wood pin type probes or Relative Humidity probes for Ambient Relative Humidity, Temperature, Dew Point, and Humidity Ratio of the environment and building materials.


Product Order Code: MRH3
Non Destructive
Comparitive 0-100
Wood Moisture Content 7-40%

















  • Digital, non-destructive moisture meter.
  • Deep signal penetration to over 25mm (1") into the materials being tested without the need to damage the surface. Signal penetration depends on material being tested and meter setting.
  • Specific gravity adjustment for wood species. 
  • External Rubber electrodes make direct contact with the material being tested for best sensitivity and repeatability.  
  • Wide range of readings for wood of 5% to 30% and 0 to 100 comparative for all other materials.
  • Backlit, large, clear, easy to read LCD display.  
  • “Hold” function enables user to "freeze" the reading. Useful for taking readings when the meter face is not visible.
  • Switchable "On" or "Off" audio warning tone.    
  • Automatic power cutoff switches "Off" when not in use.
  • Automatic default to last user setting when switched back on.
  • Battery operated (included).
  • Attaches to plug-in wood probe (optional).
  • Attaches to plug-in Tramex Hygro-i2 ® relative humidity probe for relative humidity, temperature, dew point and mixing ratio readings (optional).

The MRH3 operates on the principal of non-destructive impedance measurement. Co-planar electrodes are fitted on the base of the instrument from which low frequency signals are transmitted into the material under test, measuring the change in impedance caused by the presence of moisture. This reading is translated by the instrument into a moisture content reading.


Hygrometer mode:

When the Tramex Hygro-i2 ® relative humidity probe is plugged into the MRH3, it automatically changes to Hygrometer Mode. The Tramex Hygro-i2 ® provides the ideal solution for measurements of ambient relative humidity, temperature and dew point conditions within the building structure and in structural materials such as concrete flooring, walls etc.



Size: 6" x 3.5" x 1.5" (150mm x 85mm x 38mm)
Weight: 8.47oz (240g)
Construction: ABS Body
Power: 9 volt PP3 Battery (included)
Display: Digital / Backlit
Depth of penetration: up to 1¼"(30mm)(In wood, drywall)


Measuring range:

Reference scale for building materials: 0 to 100
Relative Humidity (with optional Hygro-i2 ® probe): 0 to 99%
Wood Non-invasive Mode: 5 to 55% MC (at SG of 0.3)
Wood Invasive Mode (with optional wood pin probes): 7 to 40%MC

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