Mortar, Cement and Fresh Concrete Rheometer, Viskomat XL
Viskomat XL, Mortar, Cement and Fresh Concrete Rheometer


Qualitest viskomat XL is a Rheometer for Mortar and Fresh Concrete up to 8 and more mm Grain Size. It fills the gap between the viskomat NT for mortar and paste with a specimen volume of 360 ml and the con¬crete rheometer BT2 with a sam¬ple vol¬ume of 20l.

The operation principle of the viskomat XL is near the same as for the viskomat NT. So a mixer formed probe is measuring the torque, and the specimen vessel is rotating. An additional scraper is cleaning the wall of the vessel.


Very dynamic speed range

The speed may be 0.001 to 80 rpm in both directions, clockwise or counter clockwise. User may define the speed in several steps, in a linear increase or decrease of speed.
As an option, an oscillating or shear stress controlled mode is possible.

High Torque Range

The viskomat XL has a torque range from 0 to 1000 Ncm with a resolution of 0.05 Ncm and accuracy better than 0.2 Ncm.

Temperature control

Temperature control is realized by a double wall specimen container, where a cooling liquid is circulating. The specimen temperature is measured with a RTD mounted inside the shaft of the probe.

High Time Resolution

The sampling rate might be set from 0.005s to 1min.

Shear Stress Control Mode

As option you may run the viskomat XL with a shear stress controlled mode. So you pre-set the torque over time, and the speed is automatically controlled to achieve the predefined torque.

Oscillation Mode

The oscillation mode gives information about the storage modulus G' and the loss modulus G'', as well as the plastic and elastic properties of your material.


The viskomat XL is controlled via a network interface. Simple connect your PC and start your Internet Explorer for full control and data transfer. No special software installation necessary.

Technical Specifications


viskomat XL


Rheometer for mortar paste and fresh concrete 6 to 20 mm

Motor Speed Range

0.0001 - 80 rpm (steady speed and speed ramp mode)

Maximum Grain Size

6 -16mm (depend on aggregate shape)

Specimen Volume

3.5L (3L usable)

Inner diameter 165mm, height 175 mm

Motor Torque

12 Nm

Motor Angle Measurement Accuracy

± 0.05 ° or better

meas. Torque Range

0 - 3000 Nmm or 0 - 10000 Nmm ( selectable)

meas. Torque resolution

0.01 Ncm

meas. Torque Accuracy

0.2 Ncm

Sampling Rate

0.005s – 1 min

Temperature Sensors

RTD PT100 1/10 DIN B

Cooling and Heating

double wall vessel connected to an external chiller


extra cabinet, 110..230V, 50..60Hz, 800W


Could be connected via a Network interface to any PC running a WEB browser based on 32 bit or 64 bit technology like Windows XP, Vista, Widows 7, OS X, and Linux. The viskomat XL may be integrated in your Intranet. To run the viskomat XL no special PC is necessary.

Controller Interfaces

4 x USB, 2 x GBit network, HDMI, ext. SATA

User Interface

Colored screen with online graphic, or external PC / tablet




Special proximity sensor with automatic stop function.


920 × 315 × 410 mm

Standard Configuration

Control unit with screen, mouse, keyboard, USB-port, Network connection, one probe for concrete and one probe for mortar and paste, one scraper, user manual.


For more information about Viskomat XL, Mortar, Cement and Fresh Concrete Rheometer, please call us at 1.877.884.8378 or Click the button below.