Sensors

Optical oxygen sensors CSOT63

The CSOT63 variants are optical oxygen sensors designed to measure oxygen concentration in both liquids and gases, as well as temperature. An input block (with galvanic isolation) is integrated in the body of the sensor, allowing for connection to INSA analyzers, or directly to process control systems with a 4-20 mA analog input, with no further components.

These sensors are used to measure the concentration of oxygen at biological WWTPs, in surface or groundwater, in water-treatment technologies, fish farming facilities, etc. They are installed in open tanks or channels, suspended by the cable, usually using the MUT14 clamp. The working position must be chosen in such a way that movement of the suspended sensor does not damage it.

• The high level of protection (IP68) allows deployment directly in the technological process, without the need to use probes or other covers.
• Accurate measurement in both still and flowing water, thanks to zero dependency on flow rate.
• Smooth surface of the plastic membrane allows self-cleaning of the sensor in flowing water (typical for WWTP activation tanks) and thus lower maintenance requirements.
• Long service life of the sensor and the membrane head, with maximum simplicity of head replacement.
• Virtually no need for recalibration.
• Resistance to the effects of CO₂, SO₂, H₂S significantly increases the reliability of measurements, especially in WWTPs.

• Downloads:
• CSOT63 dimensions
• User's manual CSOT63-66
• User's manual CSOT63-88

Optical oxygen sensors CSOT53

CSOT53 sensors are mainly used to measure and control the oxygen content in the activation tanks of biological WWTPs, in surface, underground and waste water or in fish farming facilities. CSOT53 is an optical sensor based on the principle of luminescence quenching by oxygen, fitting into a classic miniature outline (no input block integrated).

The P versions are designed for installation into fixed probes, while the L versions are suitable for use with desktop and portable instruments. We also offer a version compatible with standardized ground glass joints (primarily for BOD measurement).

• Accurate measurement in both still and flowing water, thanks to zero dependency on flow rate.
• Smooth surface of the plastic membrane allows self-cleaning of the sensor in flowing water (typical for WWTP activation tanks) and thus lower maintenance requirements.
• Long service life of the sensor and the membrane head, with maximum simplicity of head replacement.
• Virtually no need for recalibration.
• Resistance to the effects of CO₂, SO₂, H₂S significantly increases the reliability of measurements, especially in WWTPs.

• Downloads:
• Dimensions of CSOT43P a CSOT53P sensors (industrial versions)
• User's manual CSOT53

Oxygen sensors CSOT43

CSOT43 sensors are mainly used to measure and control the oxygen content in the activation tanks of biological WWTPs, in surface, underground and waste water or in fish farming facilities. CSOT43 is a classic Clark type sensor, with robust all-glass two-electrode detection system and a small-area cathode. Compared to modern optical sensors, its advantage is primarily a faster response, as well as the ability to measure very high values.

The P versions are designed for installation into fixed probes, while the L versions are suitable for use with desktop and portable instruments.

• Optimal size of the electrodes and the electrolyte supply ensures perfect linearity, excellent time stability and long maintenance-free operation, without the need for electrolyte replacement, or a third electrode.
• Extremely low oxygen consumption reduces the demands on the flow of the measured water. The sensor can work in virtually any conditions, without additional stirring.
• Smooth surface of the plastic membrane allows self-cleaning of the sensor in flowing water (typical for WWTP activation tanks) and thus lower maintenance requirements.

• Downloads:
• Dimensions of CSOT43P a CSOT53P sensors (industrial versions)
• User's manual CSOT43 (Czech)

pH sensors

Glass sensors for measuring pH integrate both the pH electrode and the required reference electrode in one unit.

Individual variants differ depending on the purpose of the sensor, mainly in terms of length, shaping of the active part and method of attachment. Sensor cables for laboratory use are terminated with a connector according to the type of instrument used.

Glass electrodes cannot be used in the presence of fluoride ions. In this case, antimony electrodes (available on request) are used. The alternative designations listed below apply to previously supplied sensors.

• Downloads:
• pH sensors dimensions
• Sensor pH 521-BNC dimensions

ORP sensors

Sensors for measuring ORP integrate both the platinum electrode and the required reference electrode in one unit.

Individual variants differ depending on the purpose of the sensor, mainly in terms of length and method of attachment. Sensor cables for laboratory use are terminated with a connector according to the type of instrument used.

• Downloads:
• ORP sensors dimensions

Conductivity sensors

Classic glass sensors with platinum electrodes (series C21, C29) excel in chemical resistance and a wide range of operating temperatures. Due to their shape, however, these sensors are difficult to clean and are therefore not suitable for measuring contaminated water - these sensors cannot be used with automatic sensor cleaning.

The CS21 sensor is better suited for industrial applications. Its robust stainless steel electrodes are arranged in one plane, which allows them to be easily cleaned (especially by the automatic mechanism of the SPO41ME and SPR41ME probes) and thus to measure even heavily contaminated samples. However, the materials used (stainless steel, PVC, Polyethylene terephthalate) limit these sensors to a less aggressive environment, with a limited range of working temperatures.

In connection with the advanced technology of INSA instruments, the listed two-electrode sensors can successfully measure even very high values of conductivity (exceeding 100 mS/cm).

• Downloads:
• Conductivity sensors - dimensions

Chlorine sensors CSCT43 and CSUT43

CSCT43 and CSUT43 sensors are amperometric membrane-based sensors designed to measure chlorine concentration (and also temperature) in water, primarily for the purpose of continuous technology control. The output is mostly not affected by other substances in the water, further advantages are easy operation and resistance to pollution. However, regular calibration is required for correct measurement (e.g. by determining chlorine using the DPD method).

These sensors are based on a pair of electrodes immersed in an electrolyte, separated from the measured environment by a membrane permeable to chlorine (but also to other gases, such as O₂, O₃, ClO₂, CO₂). Chlorine (hypochlorous acid, hypochlorite ion) is reduced at the cathode, resulting in the generation of an electric current proportional to the partial pressure of HOCl (CSCT43-R), or HOCl + OCl^- (CSUT43-R). The sensors consume chlorine (hypochlorous acid, hypochlorite ion), which is taken from the measured environment, and thus all factors influencing the rate of diffusion to the cathode surface take effect. The output current also depends on temperature, which INSA analyzers compensate based on readings from the sensor's built-in thermometer.

The measured data are somewhat different in nature from the results determined by the DPD method. Dosing chlorine in the form of gas or hypochlorites produces (simplified) hypochlorous acid (HOCl) and hypochlorite ion (OCl^-), which are in mutual balance, dependent on the pH value (see figure). If ammonium ions are present in the water, then chloramines will also appear. Hypochlorous acid (and free chlorine gas, if present) is an effective disinfectant, with a power 20 to 100 times greater than the disinfecting power of the hypochlorite ion. The CSCT43 sensor measures the concentration of elemental chlorine and hypochlorous acid, so its signal is independent of the pH value up to approximately 5.0, at higher values it then decreases according to the indicated curve. The signal of CSUT43 sensor is proportional to the concentration of both hypochlorous acid and hypochlorite ion.

When free chlorine is determined by the DPD method, elemental chlorine, hypochlorous acid and hypochlorites are determined. When determining total chlorine (total residual chlorine) using the DPD method, elemental chlorine, hypochlorous acid, hypochlorites and chloramines are then determined. Both of these values are usually higher than the value obtained by the CSCT43-R sensor.

It also follows from the above that the CSCT43-R is an ideal sensor for measurements of chlorine in swimming pools, where the disinfection efficiency of the dosed agent (i.e. the concentration of hypochlorous acid) needs to be controlled, and the pH value does not fluctuate much. The CSUT43-R sensor is suitable where it is necessary to measure the content of free chlorine and the pH value fluctuates.

• Downloads:
• CSCT43 and CSUT43 dimensions
• User's manual CSCT43 (Czech)
• User's manual CSUT43 (Czech)

Chlorine dioxide sensor CSDT43

The CSDT43 is amperometric membrane-based sensor designed to measure chlorine dioxide concentration (and also temperature) in water, primarily for the purpose of continuous technology control.

The sensor is based on a pair of electrodes immersed in an electrolyte, separated from the measured environment by a membrane permeable to chlorine dioxide (but also to other gases, such as O₂, O₃, Cl₂, CO₂, NH₃). Chlorine dioxide is reduced at the cathode, resulting in the generation of an electric current proportional to the partial pressure of chlorine dioxide. The sensor consume chlorine dioxide, which is taken from the measured environment, and thus all factors influencing the rate of diffusion to the cathode surface take effect. The output current also depends on temperature, which INSA analyzers compensate based on readings from the sensor's built-in thermometer.

• Downloads:
• CSDT43 dimensions
• User's manual CSDT43 (Czech)

Ozone sensor CSZT43

The CSZT43 is amperometric membrane-based sensor designed to measure ozone concentration (and also temperature) in water, primarily for the purpose of continuous technology control.

The sensor is based on a pair of electrodes immersed in an electrolyte, separated from the measured environment by a membrane permeable to ozone (but also to other gases, such as O₂, Cl₂). Ozone is reduced at the cathode, resulting in the generation of an electric current proportional to the partial pressure of ozone. The sensor consume ozone, which is taken from the measured environment, and thus all factors influencing the rate of diffusion to the cathode surface take effect. The output current also depends on temperature, which INSA analyzers compensate based on readings from the sensor's built-in thermometer.

• Downloads:
• CSZT43 dimensions
• User's manual CSZT43 (Czech)

Ion selective electrodes

Ion selective electrodes are sensors designed for the measurement of specific chemical ions in a solution, both in laboratory and industrial applications.

Not all ISE sensors include a reference electrode - in its absence, a separate reference electrode must be used. For industrial applications, a suitable probe or flow-through unit must be used that allows at least two sensors to be installed.

The dimensions of the industrial version of these sensors (Ø12 x 115 mm) are suitable for probes SPO41, SPO42, SPR42, SVK42, PE G3/4D, SPO41ME or SPR41ME. A laboratory version of similar dimensions is also available, with a cable terminated with the appropriate connector according to the device used.

The ion-selective electrodes supplied with our devices are sourced from third-party suppliers. More detailed information and the current availability of the variant suitable for a specific device will be specified upon request.

Reference electrodes

For sensors that do not have an integrated reference electrode, separate reference electrodes are required – this is often the case with ion-selective electrodes. Since a pair of separate electrodes is then used, industrial applications will need a suitable probe or flow-through unit that allows at least two sensors to be installed.

Commonly supplied sensors for measuring pH and ORP have the required reference electrodes already integrated, so there is no need to supplement them with additional electrodes.

Temperature sensor TTK21

Separate temperature sensors are primarily used to compensate for the temperature dependence of sensors not equipped with built-in temperature sensing. This improves the accuracy of the measurement. The measured temperature reading is usually also available as an output for the user.

• Downloads:
• Temperature sensors TTK21 - dimensions

Temperature sensors TNiK21, TNiK115

Separate temperature sensors with nickel-type sensing element are only compatible with some older types of our devices. Pay attention to the data in the table.