GESTRA Conductivity Monitoring : Manual Temperature Compensation

The conductivity limit switch type LRS is provided with a relay contact which reacts as soon as the conductivity exceeds the preselected value. Two light-emitting diodes indicate conductivity higher or lower than limit value. The limit value is continuously adjustable. The measuring range can be switch-selected, there are two ranges for each of the two versions: 0.4 to 10 mS/crn or 0.04 to 1 mS/crn for LRS 1-5b; 4 to 100 pS/cm or 0.4 to 10 VS/cm for LRS 1-6b. The effect of temperature can be compensated for manually up to a maximum of 250*C with an adjustor on the front panel.

The conductivity transmitter type LRT provides an output current of 0 to 20 mA or 4 to 20 mA which can be used as an input to the max.-min. limit switch type URS-2b, the bar-chart indicator type URA or a recorder. Two versions of the LRT are available, each with two switch-selected measuring ranges: 0 to 10 mS/cm or 0 to 1 mS/cm for LRT 1-5b; 0 to 100 VS/crn or 0 to 10 VS/crn for LRT 1-6b. The conductivity (0 to 100 %) is indicated on an integral meter. Manual compensation of the temperature up to 250 0 C is possible using the adjustor for the temperature coefficient (TK).

GESTRA Conductivity Monitoring : Automatic Temperature Compensation

Design

The system consists of the conductivity electrode type LRG 12-1, the conductivity transmitter type LRT 1-5b or LRT 1-6b and the max.-min. limit switch type URS-2b or of the conductivity electrode type LRG 16-5 and the continuous blowdown controller type LRR 1-9. 

The conductivity electrode type LRG 12-1 can be used up to PN 10 and is supplied with a screwed connection 11/4" BSP The conductivity electrode type LRG 16-5 can be used up to PIN 40 and is supplied with a screwed connection 3/4" BSP.

The conductivity transmitter type LRT 1-...and the max.-min. limit switch type URS-2b are supplied in a plastic case for installation in control cabinets. Additional field cases type CR are available for wall mounting (see page 15). The continuous blowdown controller type LRR 1-9 is supplied with a DIN case for panel mounting.

GESTRA Inductive Conductivity Monitoring

Design

The sensor consists of two toroidal-core coils in a non-conducting housing either concentrically arranged or beside one another. The housing is designed so that part of the liquid forms a closed, conductive current path through the concentric centre hole of the cores. The liquid can be considered as a common short-circuit loop of the toroidal cores.

Advantages

• Operation without electrode, i.e. no measuring errors caused by non-conductive deposits, polarization or electrode decomposition.

• High degree of accuracy, maintenance free operation.

• No capacitive influences.

• Corrosion-resistant materials.

• Sensor with protective insulation, no earthing problems.
  
  

Data Sheet