Hand-Held Moisture and Temperature Meter for Spot-Checking in Oil


Hand-Held Moisture and Temperature Meter for Spot-Checking in Oil


Hand-Held Moisture and Temperature Meter for Spot-Checking in Oil


  • Measurement independent of oil type, age and temperature
  • In-line process checking through ball valve, no need to drain the oil
  • Rugged and reliable construction
  • Excellent pressure and temperature tolerance
  • Data can be logged and transferred to a PC
  • Proven Vaisala HUMICAP® Sensor, 15 years in oil applications.
  • Compatible with Vaisala’s fixed oil moisture instruments
  • No reference oil needed for recalibration
  • NIST traceable (certificate included)

The Vaisala HUMICAP® Hand-held Moisture Meter for Oil MM70 enables reliable detection of moisture in oil.

In-Line Process Checking Through Ball Valve

The probe can be inserted directly into the process pipe through a ball valve without draining the oil in the system.

Water Activity Measurement

The MM70 measures moisture in oil in terms of the water activity (aw) and temperature (T). Water activity directly indicates whether there is a risk of free water formation. The measurement is independent of oil type, age and temperature.

PPM Calculation Included

The MM70 has an embedded model for expressing moisture as ppm in mineral transformer oil. The customer can enter up to three other oil models into the meter’s memory.

Numerical and Graphical Display

The MM70 features a multilingual, menu-based user interface and a backlit LCD display. The measurement parameters can be numerically and graphically displayed and logged into the meter's memory at the same time. An analog output option is also available.

Connection to PC

The optional MI70 Link Windows® software in combination with a USB connection cable is used to transfer logged data and real time measurement data from the MM70 to a PC.

Proven Vaisala HUMICAP® Technology

The MM70 incorporates the latest generation of the Vaisala HUMICAP® Sensor, developed for demanding moisture measurements in liquid hydrocarbons. The sensor’s excellent chemical tolerance provides accurate and reliable measurement over the measurement range.

Speedy Service - Once a Year

The meter can be recalibrated by sending the probe to Vaisala Service

Multi-Probe Operation

One or two probes can be connected simultaneously. Maintenance teams can use additional Vaisala dew point or relative humidity probes for other tasks. For example, a dew point probe is ideal for checking the moisture inside washed and dried oil tanks.

Types of Moisture in Oil Products - Portable