Sigma Hellas Ltd contact information

If you still have problems, please let us know, by sending an email. Thank you!

Working Hours

Mon - Fri: 08:00 - 16:00 (EET)
Sat: Closed
Sun: Closed



Electrical conductivity is the ability of a material to carry electrical current. In water, it is generally used as a measure of the mineral or other ionic concentration. Conductivity is a measure of the purity of water or the concentration of ionized chemicals in water. However, conductivity is only a quantitative measurement: it responds to all ionic content and cannot distinguish particular conductive materials in the presence of others. Only ionizable materials will contribute to conductivity; materials such as sugars or oils are not conductive.

Typical conductivity Values

Conductivity Resistivity
Pure Water 0.055 μS/cm 18.3 MΩ -cm
Distilled Water 0.05 μS/cm 2.0 M2.0 MW -cm -cm
Power Plant Boiler Water 1.0 μS/cm 1.0 M1.0 MW -cm -cm
Pure Mountain Stream 10 μS/cm 100 KΩ -cm
Good Tap Water 50 μS/cm rarely used
0.001 N Potassium Chloride Solution 1409 μS/cm rarely used
Maximum for Potable Water 1500 μS/cm rarely used
Sea Water 53 mS/cm rarely used
10% Sodium Hydroxide 355 mS/cm rarely used
10% Sulphuric Acid 432 mS/cm rarely used

With the reverse osmosis process, water is forced in a semi-impermeable membrane leaving the impurities behind. This process is capable of removing 95-99 % of TDS (total disolved solids), providing pure or ultra-pure water.

DAX conductivity controller a multi parameter analyser / controller

The DAX is designed to be an extremely flexible, easy-to-use, multi-parameter analyser/controller.

Just select the parameter you want to measure from the LCD menu on the inside front cover. Choose from conductivity, pH, ORP, or  flow. The DAX gives you access to two displays. A bright LED numeric display with a bargraph on the outside front panel, and a two-line, 16-character LCD display on the inside. The LED readout can be seen from several yards away. The distinctive color-coded bar graph makes diagnosing pump and alarm malfunctions easy. It will immediately indicate if you are within the process parameters you’ve set (green), if the control relays are on (yellow), or if the process is in alarm conditions (red). All configuration and control functions are performed on the LCD menu inside the front panel.

You’ll also be able to perform calibration functions and check temperatures (where applicable) from the front panel LED. Since this routine maintenance doesn’t require opening the front panel to access the main menu on the side, configuration settings can’t be changed by mistake. You can perform process and temperature calibration from the LCD menu, where calibration slope, temperature, and efficiency are displayed.DAX  controller/analysers provide control of external devices using two independent control relays. A third relay is preset to act as an alarm, but can also be used as a process control relay. It has both high and low ON setpoints, with adjustable OFF setpoints.

Factory-set for bidirectional control, both control relays can be set for either rising or falling process with easily programmed On and OFF setpoints. Each control relay has a built-in independent cycle timer, with field-set ON and OFF times. This feature enables tighter control of batch processes by eliminating chemical overshoot.

The DAX is packaged in a rugged NEMA 4X polycarbonate enclosure, making it ideally suited for heavy-duty applications, such as industrial wastewater neutralization, municipal water and wastewater, pulp and paper,and process control.

Each DAX comes complete. There are no extra costs associated with buying boards for different applications, or buying components to achieve NEMA 4X ratings. A universal mounting kit is included with each unit for surface panel and pipe mounting.


  • pH, ORP, conductivity, and flow parameters available as choices.
  • Easy-to-read 4-digit LED display
  • Bright colour-coded bargraph display
  • No extra cards or options required
  • Relay cycle on/off timers
  • Two control relays and high/low alarm relay
  • Two 4-20 mA outputs with range expandability • 1/4 DIN NEMA 4X enclosure
  • Universal mounting hardware provided for surface, panel, and pipe mounting
  • Snap-on terminal connectors

On-line industrial type sensors
Two-electrode E. Conductivity probes

  • SI 308T  In-line E. Conductivity probe + Pt100 Cell constant: K=0.01
  • SI 301  In-line E. Conductivity probe Cell constant: K=1
  • Body: PVC
  • Electrodes: 316 S/S
  • Temperature sensor: Pt100Thead: 1” PVC
  • Operating temperature: 50C maximum
  • Operating pressure : 3 bar max at 25C
  • Cable length 3m
  • Applications: high purity water
  • Input from 2-electrode cells

Kcm2 0.01 0.10 1.00 10.00
Range      200nS   2000nS    20.00μS
200nS     2000nS  20.00μS   200.0μS
2000nS  20.00μS  200.0μS     2000μS
20.00μS  200.0μS  2000μS   20.00mS

  • electrodeless E.Conductivity probes
  • SI 315 & SI315.1  In-line E.Conductivity probe + Pt100
  • Cell constant: K=1 approx
  • SI 301  In-line E.Conductivity probe Cell constant: K=1
  • Body: PVDF in contact with the liquid
  • Temperature sensor: Pt100 integrated
  • Operating temperature: 110C maximum
  • Operating pressure : 3 bar max at 25C
  • length 200mm
  • Diameter 34mm