A microwave meter for rapid determination of moisture content in wet cement and concrete.

The James Cementometer™ represents a break-through in modern
moisture measurement technology. By utilizing the latest
microwave and microprocessor science, the Cementometer™
can determine the moisture content of freshly mixed cement, concrete, and mortar. Simply insert the prongs of the probe into the
material to be measured and instantaneously the water cement
ratio is shown on the easy to read display.

The Cementometer™ Microwave moisture meter uses a two
prong sensor to measure the complex dielectric constant of the
material in contact with the prongs. As the dielectric constant of
water is four to eight times greater than most aggregates and
cements, changes in water content directly effect the sensor output.
An average of five to ten readings is normally taken in order
to ensure a valid reading. This output is then converted by the
integrated microprocessor and moisture content is displayed
directly.

Two units are available to encompass the full range of water
cement ratio’s found in wet concrete. The Cementometer™ Type R
handles normal water cement ratio’s with its two prong probe.
The range of this instrument is approximately 0.35 to 0.65
water/cement. Cementometer™ Type L handles low water/cement
ratio’s with its five prong probe. The range of this instrument is
approximately 0.25 to 0.5 water cements.

The units come calibrated for standard type I, II, and III
cements. It can also be programmed with up to ten different mix
design by the user. For highest accuracy, the user should program
the unit for the material being used. The Cementometer™ Type R
has simple to use calibration process that rapidly creates the user
programs without the need for external computing devices.
Finally, the Cementometer™ can store over 150 readings. Storage
is complete with the time and date for future reference. Data can
be recalled via RS-232 interface to a personal computer running