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Sensor Measures Dissolved Nitrate In Water

Featuring a precision nitrate ISE electrode sensor with an integral self-cleaning sprayer, the new HYDRA Nitrate Analyzer System from Electro-Chemical Devices, Inc. (ECD), offers superior measurement, monitoring and control with virtually no maintenance.

The highly intelligent HYDRA Nitrate Analyzer System measures the concentration of dissolved nitrate as nitrogen (NO3–N) in water. The sensor uses two electrodes to determine the NO3–N concentration: a nitrate ion electrode and a chloride ion electrode. An optional electrode is also available for pH measurement.

The system’s HYDRA Analyzer is configured to periodically actuate a cleaning cycle using the integral spray cleaner in the nitrate sensor, minimizing the formation of biofilms or other coatings on the electrodes and keeping maintenance to a minimum. The cleaning cycles feature a user configurable period and duration. During the cleaning cycle the 4-20 mA output is held at either a preset value or the last value.

While useful in all types of water treatment applications, the HYDRA Nitrate Analyzer System is especially well suited for municipal wastewater treatment plants. Nitrogen primarily enters a municipal wastewater system as ammonia/ammonium compounds. Nitrification oxidizes the toxic ammonium ion into a much less toxic nitrate ion using an aerobic activated sludge process.

De-nitrification reduces the nitrate ion (NO3-) to nitrogen gas (N2) through an anoxic reaction in the same treatment basin or in a separate anaerobic digester. The NO3–N measurement helps optimize the methanol being fed to the digester, which minimizes cost and provides trend measurement of the total nitrogen (TN) in the effluent.

The nitrate ion electrode provides the primary measurement. A second electrode measures the Chloride ions in the sample. The HYDRA Analyzer subtracts the appropriate amount of signal from the nitrate measurement for accurate monitoring. The sensor also detects temperature, and the analyzer provides a temperature-compensation calculation for superior measurement accuracy.

The rugged nitrate sensor offers 1.25-inch NPT rear facing threads for attaching an extension/immersion tube for easy installation from catwalks or handrails. Internal signal conditioning allows the sensor to be mounted up to 200 meters from the analyzer. The sensor is extremely low-maintenance, featuring a movable electrode guard to facilitate easy electrode replacement when necessary.

ECD’s HYDRA Nitrate Analyzer System measures nitrate and chloride in concentrations from 0.1 to 1000 ppm, pH from 0 to 14 and temperature from 0 to 50°C (32 to 122°F). Accuracy is ±3 percent of reading with a response time of T90 1 minute.

Featuring a backlit LCD display that provides up to 4 lines of text and graphics, the HYDRA Analyzer includes two 4-20 mA outputs with two SPDT alarm relays. Input power is 110/220 Vac. It is housed in a rugged NEMA 4X enclosure.

www.ecdi.com

Medical Sensor Is Put On Blood Bags

Schweizer Electronic AG, situated in Schramberg, Germany, and SIEMENS AG Österreich, with registered offices in Vienna, Austria, have agreed to extensive cooperation for the manufacture and marketing of RFID transponders with the integrated sensor technology known as “SEAGSens”. Schweizer Electronic is responsible for the manufacture of the transponders developed in collaboration with the Hochschule Offenburg (Offenburg university) and SIEMENS. SIEMENS will assume the distribution and marketing. The SEAGSens will be used in seamless temperature monitoring, tracing and the clear identification of blood bags, medications or foodstuffs, among others. Schweizer Electronic is to operate the RFID business in the context of a “Schweizer Tracking and Tracing Solutions” business unit.

After having completed extensive tests and pilot projects, Schweizer Electronic has now finalised the qualification of the SEAGSens (see pictures). The first series production order has already been received.

In principle, the RFID-based measuring instrument monitors and verifies temperatures as required in this logistical application of blood products. Reliability is the all-important decisive factor here. The SEAGSens fulfils the highest requirements of clinics and blood banks. The temperature-based quality assessment of donor blood on their entire route from the donor to the patient markedly reduces the discard rate of blood products which leads to considerable cost savings.

In addition, the clear identification of the stored blood effectively prevents the serious consequences of incorrect blood transfusions caused by mistaking blood bags. The same technology can also be used to monitor the transport and logistical processes of other industries and applications for which temperature is of critical importance.

To achieve the required quality level of temperature-sensitive pharmaceutic products, monitoring of the complete cold chain has to be ensured. Therefore, Schweizer Electronic designed the requirements for a tracking and tracing system for blood products in close collaboration with Siemens AG Österreich and ‘Universitätsklinik für Blutgruppenserologie und Transfusionsmedizin’ located in Graz.

The complete temperature profile of blood bags has to be monitored from vein of donor to vein of recipient. Thus, the monitoring device must be able to withstand the centrifugation processes necessary for blood fraction (up to 5,000 G) without malfunction. The operation costs per run have to be low.

Together with Siemens AG Österreich and University of Offenburg Schweizer Electronic developed SEAGsens, a temperature data logger with RFID frontend.

How does it work?
A digital sensor is measuring the temperature very accurately at a freely selectable time cycle. The microcontroller is analysing the temperature/time data and stores up to 30,000 measurement readings in a memory chip. The memory can be read out contactlessly at any time via the RFID wireless interface (HF frontend). Schweizer Electronic developed a special housing and battery technology to ensure centrifugation ability. The qualification process and the clinical field test have been terminated successfully. The benefit: monitoring of long periods through high memory and battery capacity.

The SEAGsens RFID sensor tag provides highest level of functionality, safety and quality. Due to the long operation time, costs per run are comparatively low. The integrated battery allows a continuous useability of more than 3 years. The temperature focused quality control reduces the wastage rate of blood products considerably. By the unique identity of each single blood bag, incorrect transfusions with all their harmful consequences are efficiently eliminated.

www.schweizerelectronic.ag

www.siemens.at

Liquid Sensor Has No Moving Parts

A precision off-the-shelf liquid level sensor, developed for motorsport, military and industrial applications the ‘R-Series’ is now available from Gill Sensors. The sensor has no moving parts, utilising advanced capacitive technology to accurately monitor the liquid level.

Compatible with fuel, oil, water and other specialist liquids, the R-Series liquid level sensor features an SAE 5-bolt flange mount as standard and is manufactured to the end users’ exact length requirement, avoiding the need for any mechanical adjustment by the user. With fully integrated electronics producing a configurable 0-5V analogue output, the R-Series is seen as an ideal ‘drop-in’ solution for most liquid level applications.

In addition to the standard R-Series sensor, Gill Sensors has also introduced an ‘Rxl’ variant for applications where a very long sensor is required. This variant of the R-Series utilises the same SAE 5-bolt mounting pattern but introduces additional mechanical strengthening features to support the longer probe. This sensor targets industrial applications that require precision liquid level measurement of storage tanks up to 3m in depth, says the company.

www.gillsensors.co.uk

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Continuous Liquid Level Sensor Uses Magnetostrictive Technology

OleumTech today announced the release of the H-Series, hard-wired continuous level sensors, which complements its existing wireless liquid level transmitter offering. The H-Series is a digital level sensor based on a field proven magnetostrictive technology, which makes it ideal for Oil & Gas, Food & Beverage and other level measurement applications requiring process control, leak detection or inventory control.

With a low power design, H-Series sensors can be multi-dropped on a RS485 network, providing Modbus connectivity to a RTU or PLC controller. By combining low power requirements with high resolution of 0.01″ across full span, the H-Series provides the ultimate performance and reliability.

“The new liquid level solution is ideal for short distance runs to the RTU or existing legacy installs where conduit and wiring is available,” said Vrej Isa, COO at OleumTech. “But it’s the innovative packaging with the ease of installation that will set us apart from the competition.”

The Liquid Level Sensor is capable of providing product level, interface level and temperature measurement in virtually all tank sizes (up to 60 feet tall) in a variety of liquids such as crude oil, solvents, water, diesel, kerosene, gasoline and other media. The H-Series is available in a rigid stainless steel or flexible PVDF package.

The H-Series design meets applicable regulatory requirements for use in hazardous environments. OleumTech additionally offers an optional barrier board that limits the current, voltage, and total energy delivered to the sensor in a hazardous area or flammable environment. The barrier boards also provide extra protection to the level sensor from lightning strikes or any surge damage.

www.oleumtech.com

Level Sensor Built for Bulk

The microwave barrier VEGA‘MIP’ (Microwave Impulse Point-level) is especially designed for the needs of the bulk handling industries. It can be applied to bulk solids or liquid level detection, in plastic vessels for example, or object detection – such as vehicle positioning/warning and oversize/height alarms on conveyors etc. As this is a non-contact measurement, VEGAMIP 61 has no direct contact with the medium, providing reliability for abrasive, aggressive or high temperature applications. In the case of metallic or conductive vessels, VEGAMIP can measure from the outside through a non conductive microwave permeable window, e.g. in ceramic, glass or plastic materials.

VEGAMIP consists of a transmitter VEGAMIP T61and one or several R61 receivers for wider areas. The adjustable sensitivity receiver measures the attenuation of the microwave signal and outputs a relay switch. It has a very wide dynamic range, borne from the pedigree of over 250,000 microwave level devices sold world wide. The wide sensitivity range adds to reliability, especially when operating conditions are difficult, which means it still operates consistently with dirt, dust or build up. Operating ranges are up to 100m.

VEGAMIP can be used as a maximum or minimum sensor, switching delays can be set between 0.1 and 20 s. VEGAMIP is fully integrated into VEGA’s plics® modular system. This means there are a range of plastic, aluminium or stainless steel housings, as well as different antenna systems and process fittings available, allowing configuration of the sensor precisely to specific user requirements.

Micropulse: Clean Enough to Eat off of

The Micropulse SF fill level sensor provides continuous, absolute fill-level measurement in applications that require adherence to the strictest standards of hygiene and cleanliness. Sensors in a sanitary manufacturing facility must be cost effective, have minimum impact  upon production, and must not negatively impact the cleanliness or quality of the foods (or products) being manufactured. Made from corrosion-free stainless steel with rounded edges and minimal crevices, the Micropulse SF meets the highest international hygiene standards and fulfills strict food industry requirements. Certified to 3-A and EHEDG sanitary standards, the sensor is 100% stainless steel to ensure top sanitation standards and long-term service life.

Benefits include:

• Chemically neutral for all liquids
• Compensates for surface foam to deliver reliable, accurate fill level values
• Adjustment-free installation
• Easy to clean in installed state (CIP – Clean in Place)
• Withstands process temperatures up to 130°C (SIP – Sterilization in Place)
• Standard analog interface ensures wide controller compatibility and flexible installation
• International certification ensures global acceptance
• Highly precise measuring technology is ideal for filling or dispensing applications

The industry-standard Micropulse SF fill level sensor uses field-tested magnetostrictive technology to provide highly-precise fill level measurement. Noncontact measurement technology ensures unparalleled reliability and performance. Its continuously-variable analog output signals allow for easy connection to control systems.

www.balluff.com

Optic Level Sensor for Harsh Environments

GEMS Sensors & Controls has launched its new 950 Electro Optic Level Sensor (ELS) for a wide range of applications and industries. According to Gems, the new miniature, low cost ELS-950 was developed to perform in harsh environments with features such as an over-molded electronics insert, TPE insulated wires, and fluorosilicone O-ring seals to create a watertight, environmentally resistant assembly.

The ELS-950 is the next generation of the 900 series, as it is built on the proven technology of its predecessor line. Additionally the small, solid state sensor is durable enough to handle almost any application or temperature.

Gems says the ELS-950 is suitable for applications such as OHV, Medical diagnostic, sterilizer, and dialysis equipment; low lubricant warning on machine tools, and generator sets; construction, agricultural, and material handling equipment; coolant reservoir monitoring/warning and OEM food and beverage applications.

www.gemssensors.com

NEW ISOLATION VALVES ADDED TO GEMS FAMILY

Gems Sensors & Controls announced their new K Series inert isolation solenoid valves. Constructed from chemically inert materials such as: PTFE, ETFE, EPDM, FKM, FFKM, PEEK, PPS and PSU; the K Series of isolation valves is an excellent choice for any application requiring various levels of chemical resistance and/or sample purity. Liquid Chromatography, Gas Analyzers and Water Quality Testers are just a few of such applications.

Offered in multiple body sizes, port configurations, wetted body and diaphragm materials; the K Series  is a truly modular platform of direct acting round bodied solenoid valves allowing for superb power, flow, durability and life optimization. This line of inert valves is comprised of three groups: KS Series are 2-way valves with an MOPD of 20 PSIG;KM/KL Series are available in 2-way and 3-Way Directional configurations, with MOPDs up to 30 PSIG; and KV/KW Series offer 2-Way and 3-Way Directional configurations, with MOPDs as high as 20 PSIG.

http://www.gemssensors.com/

Combination Liquid Level and Temperature Switch

A liquid level and temperature switch was designed into one assembly to reduce the cost of a fluid system. Tempco can design a custom sensor to meet many applications such as industrial and commercial degreasers and hot liquid dispensing machines.

Liquid Level Sensor Options
The liquid level sensing can be obtained using magnetic floats and switches, or the conductivity method. The conductivity method uses the simple concept of the conductive property of liquids to complete a circuit and cause an external control relay to actuate.

Temperature Sensor Options
Thermocouples, RTD’s, thermistors and thermostat switches with an assortment of accuracies can be incorporated into the assembly.

Tempco Electric Heater Corporation designs and manufactures electric heating elements,
temperature sensors, temperature controllers and turnkey process heating systems.

Tempco
www.tempco.com

Baumer Introduces Complete Line of Capacitive Sensors

Southington, Conn. — Baumer has introduced a complete line of Capacitive Sensors capable of penetrating through packaging materials such as plastics, glass, cardboard, foam, and other substrates. These sensors are available in a range of housing sizes and designs, and offer extended sensing distances to facilitate installation.

Installed outside of container walls, Baumer Capacitive Sensors do not require direct contact with the target substrate, a feature that protects the sensor from damage and ensures process safety and sensor life expectancy. This non-invasive method of detection also ensures that the sensor’s housing cannot contaminate the target material.

Baumer Capacitive Sensors are available in cylindrical, rectangular and special designs. Models are available for use in limited space applications, and for performance in ambient and elevated temperatures. Possible target substrates include plastics, glass, ceramics, porcelain, clay, stone, wood, paper, cardboard, pellets, powders, and foods. These sensors are used in packaging, PCB fabrication, printing, rubber/plastics fabrication, robotics and handling, transportation, warehousing, food and drug processing, medical device manufacturing, cosmetic production, wood processing, metalworking, oil and gas processing, water treatment, and textile production.

Baumer
www.baumerelectric.com/usa

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