Brochure Operation Manual

The CM100 can take single or multiple, automatic, measurements of the conductivity of 100 cells and the user has the flexibility to choose the measurement parameters.

The CM100-2 Conductivity Meter was designed specifically for the measurement of electrolyte leakage from plant tissue.

The advantages of the CM100 over single cell conductivity meters are that multiple, nearly simultaneous, measurements can be made on one hundred individual specimens. This allows the various leakage rates to be quickly and directly compared under the same conditions in a spreadsheet.

The CM100 is not intended to replace single cell conductivity meters for applications which may require higher accuracy measurements.

The CM100 has many unique Features and Benefits:

A hinged lid, with gas struts, keeps the workspace required to a minimum.
The probes are housed in a recess and so are protected from mechanical damage.
Two sample tray sizes: 1.5 and 3.5 ml wells.
The measurements are transferred to a PC using a USB mass storage device (memory stick/ flash drive/ pen) in CSV format compatible with Excel ® and other software.
Only 1.5ml of water is required per small well enabling accurate measurements on small samples of plant material.
The power supply is 12V DC so the unit can be powered from a 12V battery or solar panel for field use. A mains power adaptor for 110/ 220 VAC operation is supplied.
A robust housing made from aluminium for a long service life.
The electrodes are enclosed in an epoxy housing so the stem of the electrodes are insulated, making the conductivity reading independent of the water level in each well (assuming there is sufficient water to fully immerse the electrode).
Temperature compensation (conductivity changes by 2% / °C) using a temperature sensor in the 101st well to measure the actual water temperature, makes measurements taken at different temperatures directly comparable. The measurements are referenced to 25°C.
The CM100 has a large (5.7 inch) built in touch display and is stand alone, so it does not require a PC for operation, ensuring it will not become obsolete as new Windows ® operating systems are released

The CM100-2 is a high quality instrument designed with the direct input of practising seed scientists which combines sophisticated features with ease of use.



Number of cells 101 (10*10 matrix) + one for temperature compensation
Free volume of wells 1.5 ml/ 3.5 ml (both sizes are supplied)
Electrodes Stainless steel
Measurement range AUTO ranging
Conductivity range 1uS - 999uS
Measurement frequency 1kHz
Temperature compensation 2% / °C (over the range of 15-35°C)
Reference temperature 25°C
Operating temperature 15-35°C
Storage temperature 0-50°C
Measurement interval 1 to 60 minutes
Number of measurements/ cell 1 - 100
Time to measure 100 Cells < 30 seconds
Display 5.7" Graphic LCD with backlighting
Internal storage 10 000 measurements (100*100)
Case Aluminium
Dimensions 330*342*135mm (W*D*H)
Weight 7.5kg
Finish Epoxy powder coating
PC interface USB mass storage device (memory stick/ flash drive/ pen) Excel ® CSV file format
Power supply12V @ 250mA. A mains power adaptor for 110/ 220 VAC operation is supplied.

Specifications are subject to change without prior notice. EXCEL and WINDOWS are registered trademarks of Microsoft Corp


Touch Display

The CM100-2 has a user friendly menu system and the screen is simply touched with a stylus.

The right hand side of CM100-2 screen shows the measurement parameters.

Touching the required parameter opens a numeric keypad allowing a new value to be entered and the test Duration
is automatically updated.

All the commands are on the left hand side of the screen.

When measurements are in progress a Display option
is added to the screen allowing the user to view all the
measurement values in real time.

CSV Export

The CM100-2 measurements are transferred to a PC using a USB mass storage device (memory stick/ flash drive/ pen) in CSV format compatible with Excel ® and other software for analysis and graphing.

Graph Courtesy of Dr. James Wesley-Smith Electron Microscope Unit, University of Natal DURBAN, SOUTH AFRICA


Uses of conductivity measurements

Seed testing

Measurement of electrolyte leakage after exposure to defined stress is a well-established, rapid and simple test of seed quality and viability. Conductivity measurements have also been used successfully to reveal the state of embryonic axes excised from both recalcitrant and orthodox seeds and subjected to various conditions. Similarly this technique can be used to assess the condition of pollen and fungal spores.

Stress injury

Exposure to a range of environmental stresses often leads to injury of cellular membranes. This damage leads to leakage of solutes from the cell. Leakage of electrolytic solutes into the bathing solution has, for many years, been used as a simple and informative tool to measure damage caused by chilling, freezing, heat shock, dehydration, air pollutants and osmotic shock.

Screening for tolerance

Differences in the ability to withstand a particular stress among different genotypes can be assessed by the amount of leakage after exposure to that stress. This has been used to test for drought- and cold-resistance of cultivars of many crop and forestry species.


Why conductivity measurements?

  • Measuring conductivity of leachate from plant tissue is a long-standing method for estimating membrane permeability in relation to environmental stress, associated mycoflora, growth and development, and genotypic variation.

  • Measurement of leakage of electrolytes is also a well-established method of assessing seed quality. Leakage measurements have been carried out on a range of other tissues such as fungal spores and pollen and on material such as lichen, moss, fern fronds and the leaves of higher plants.

  • Additionally, decrease in conductivity of liquid culture media can be used to assess growth rates of micro-organisms. Leakage measurements can be a useful tool for those involved in academic research as well as in practical fields such as agriculture and horticulture. Conductivity measurements also have their place in pollution studies.