9-in-1 Temperature-Humidity Meter with Pin/Pinless Moisture Meter


9-in-1 Temperature-Humidity Meter with Pin/Pinless Moisture Meter

The super-versatile #RHMG650 is ideal for water damage restoration contractors, facilities maintenance professionals and HVAC system installers/technicians.


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  • Measures 1) ambient temperature, 2) relative humidity (RH), 3) absolute humidity (in mg/L or g/m3), 4) GPP (mixing ratio—in grains per pound or g/kg), 5) relative moisture level using the pinless sensor, 6) absolute moisture level using t
  • Stores/recalls 20 pairs of temperature and RH readings
  • Adjustable high and low alarms for RH, relative moisture level and absolute moisture level
  • Backlit LCD with 3-digit primary readout + 4-digit secondary readout
  • 33% and 75% #HR33 and HR75 reference salts are available to calibrate RH measurement in the field
  • Min/max memory + data hold
  • Auto power off
  • Specifications


    • Ambient temperature measurement range/accuracy: -20° to 167°F (-29° to 75°C)/±3.6°F (±2°C)
    • RH measurement range/accuracy: 0 to 100%/±2.5% from 11 to 90%RH; ±3%RH elsewhere
    • Absolute humidity range: 0.5 to 240mg/m3
    • GPP range: 0 to 999 GPP (0 to 160g/kg)
    • Relative/absolute moisture level range: 0 to 99.9%
    • Pinless moisture measurement depth: 0.75 in. (19mm)
    • Remote moisture probe measurement accuracy/resolution: ±3%/0.1%
    • Remote probe pin length: 0.3 in. (8mm)
    • Dew point range: -76° to 140°F (-60° to 60°C)
    • Atmospheric pressure range: 30 to 120 kPA
    • Vapor pressure range: 0 to 20 kPA
    • Sampling rate: 2X/sec
    • Memory capacity: 20 pairs of readings
    • Auto power off: After 30 minutes of front-panel inactivity
    • Operating temperature: 32° to 110°F (0° to 43°C)
    • Weight (without battery): 6.2 oz. (175g)
    • Power source: "9V" battery (included)


    • External pin-type moisture probe
    • Battery
    • Soft pouch
    • 1-year limited warranty


    • 7.3 x 2.8 x 1.4 in. (185 72 36mm)


    Do the pins have to actually go into the material?

    For the most accurate reading possible, the pins should be inserted into the object. Do not press the pins too hard. 

    Can my moisture meter be used on bamboo?

    Our moisture meters are not calibrated specifically for bamboo. You will need a moisture meter with an adjustable specific gravity setting. At this time we do not carry such a meter.

    Can my moisture meter be used on ceramics or fiberglass?

    Our moisture meters are not calibrated for ceramics or fiberglass in terms of WME readings. However, our pinless moisture meters could give relative readings on these materials..

    Are there any pinless meters which measure WME (wood moisture equivalence)?

    All of the pinless sensors on our moisture meters provide REL (relative) readings only.

    Are there any moisture meters which have a NIST Certification?

    We currently do not offer any type of certification for our moisture meters. They would need to be sent to a certification lab for that.

    Which models of temperature/humidity meters are calibrateable?

    The following models have a calibration feature: EP8703, EP8706, EP8709, EP8710, LRTH185DL, LRTH185DL1, WBGT8758, WBGT8778, DTH3007SD, RHMG650, RHMG700DL

    My instrument is calibrateable. Do I need any additional accessories to perform the calibration?

    Some instruments do require a 33% and 75% salt bottle to perform the calibration. The following models use the HR33 and HR75 bottles: DTH3007SD, EP8703, EP8706, EP8709, EP8710, LRTH185DL, LRTH185DL1, ...
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    Prop 65

    ⚠ WARNING: This product can expose you to chemicals including di2-ethylhexylphthalate (DEHP), which is known to the State of California to cause cancer and birth defects or other reproductive harm. For more information go to www.P65Warnings.ca.gov.