ARGES Nitrite Sensor
The Intelligent Submersible Nitrite Sensor By Keynes Controls, is a submersible sensor that has been designed to simplify the acquisition of water quality measurement parameters into any platform that supports real-time reporting, data logging operations. The sensor element is isolated between measurements in order to prolong its active life and reduct power.
The Keynes Controls submersible ARGES Nitrate and Nitrate sensors are used to monitor levels in waterways along with other water quality sensors.
The ARGES Nitrite Sensor by Keynes Controls can be used for statutory limit monitoring applications.
Product Features
| TYPE | RANGE (Typical levels) |
| Solid state ISE sensor. | |
| Measurement range: | 0.5 to 460 ppm |
| Nitrite Resolution: | 0.05 ppm |
| Nitrite Accuracy: | +/- 5% of Reading or 2 ppm |
| Built-in Digital Networks |
SDI12 / RS485 / MODBUS (16 & 32 Bit Registers) |
| Sensor life: | Re-calibrate after 5000 hours (3 months) |
| pH Range | 4.5 - 8 |
| Isolated Electrodes | |
| Sensor Element | Isolated between measurements |
| Interference IONS | CN- |
Measurement Integrity
All of the ARGEs sensor range have the serial number and the last calibration date stored internally. The user can access this information for reporting purposes. The sensors can be redeployed at any time with the calibration and serial number records are retained in the sensor.
ISOLATION
The sensor element of the Nitrite Sensor is isolated when not to required for any measurements. This prevents contamination of the sensor element and maintains the long active life of the device.
When no measurement is being made the sensor is in low power mode.
Calibration Summary
The sensor is supplied pre-calibrated.
The ARGES Nitrite Sensor by Keynes Controls is typically calibrated at 2 points. A Zero point which uses distilled water, and the high end calibration point using one of the calibration standard solutions.. The overall accuracy of the sensor will depend upon how well the sensor is calibrated. For optimum results calibrate the sensor at the same temperature as the solution under test.
The free issue QLOG software enables the calibration points to be entered into the sensor.
Storage and Handling
When not in use the ARGES Nitrite Sensor by Keynes Controls can be stored dry for a long period of time without any degradation in performance. Should the sensor not be used for a considerable length of time then soak the sensor in a low Nitrate concentration solution for several hours before use.
Storage temperature range : -2 to 60 Degrees Celsius.
Further Information
The majority of Nitrite in groundwater in the UK is derived from diffuse pollution from agriculture, with the rest from sewage sludge disposal to land, atmospheric deposition and point sources.
Nitrite levels in our water resources have increased in many areas due to applications of inorganic fertiliser and animal manure in agricultural areas. The regulatory limit for nitrite in public drinking water supplies was set to protect against infant methemoglobinemia, but other health effects have not been considered.
Nitrite Pollution in drinking-water
The most common sources of both nitrate and nitrite in water include agricultural activities (inorganic fertilisers and manure), wastewater treatment, nitrogenous waste products from humans and discharges from industrial processes and motor vehicles.
Nitrate and nitrite are naturally occurring ions that are ubiquitous in the environment. Both are products of the oxidation of nitrogen, as part of the cycle required by all living systems for the production of complex organic molecules, such as enzymes and other proteins.
When present in rivers, nitrite is well known to be toxic to almost all living creatures. This is due to its impact in decreasing the oxygen-carrying capacity of blood. In infants, this phenomenon is called blue baby syndrome; in fish, it is known as brown blood disorder.
A key requirement for treating drinking-water to reduce the risk of methaemoglobinaemia is disinfection to eliminate pathogens and to convert nitrite to nitrate. Therefore, drinking-water treatment methods focus on the treatment of nitrate, because nitrite is readily converted to nitrate by many disinfectants. However, nitrite can also be formed during chloramination in some water systems with a long retention time if nitrification occurs.
Common Sources
Urban areas where either large numbers of on-site sanitation facilities/leaking sewers or intensive agricultural activities can result in significant contamination of groundwater used as a source of drinking-water.
Product Specifications
| DISSOLVED Nitrite | ENVIRONMENTAL CHARACTERISTICS | |||
| Range | 0 - 460 ppm | Temperature Range: -6 to 55 Degree Celsius | ||
| Resolution | 0.01 ppm | Ambient Range: 0 - 50 Degree Celsius | ||
| Accuracy | 0.15 % Reading | Water Temperature: 1 to 40 Degree Celsius | ||
| Maximum Depth: 5 m | ||||
| Process Electrodes: | Solid State | |||
| PHYSICAL DIMENSIONS | ||||
| Length x Diameter: 22 x 220 mm | ||||
| Weight: 97 g | ||||
| Settling Time |
|
Maximum Depth : 20 m | ||
| Wiper Trigger | SDI12 Command | aM! | ||
| Built-in Network Types: | ||||
| Excitation | Galvanic | SDI12 / RS485 / MODBUS over 485 | ||
| Housing | 316 Stainless Steel / PVC | |||
| Sensor Connector | Gold Plated / Wet mate | Power Requirement | ||
| Voltage Range: 10-18 V DC | ||||
| Data Output | - ppm | Standby Current: 0.9 mA Typical | ||
| Reading: 24 mA Typical |
Please Note: The ARGES Nitrite Sensor by Keynes Controls is pre-calibrated at the factory
Supported Commands
Most Used Commands - SDI12
| Description | Master | Instrument Response |
| Start measurement | aM! | a05\r\n where 05 = time delay before measurement sent |
| Send ID | al! | a14KEYNESCOISO000014\r\n Part description assigned by Keynes |
| Address Query | ?! | Where a = ID number - 0 - 9 (standard) / (a..z) Enhanced SDI-12 0 - 9 / a - z for RS485 |
| Change Address | aAb! | where a = Initial address and b = Final address |
| Start Measurement | aM! | Make a measurement - a = address of sensor Example 1M! starts a measurement for sensor with ID=1 |
| Concurrent measurement: Used for starting a measurement for all the sensors in a SONDE or on a digital network. |
aC! | Start a measurement for sensor on address 'a'. |
| Read Serial Number | aXSN! | Instrument Response a+Serial-number |
| Calibration Date | aXCD! | Instrument Response a+date |
Commonly used with: Turbidity, Potassium, Tryptophan, Ammonia Sensors.
The Submersible Dissolved Oxygen Sensor by Keynes Controls monitors the levels of Dissolved Oxygen in water. The ARGES Dissolved Oxygen Sensor readings can be affected by changes in temperature and salinity. This sensor is frequently paired with CDOM, pH, and other temperature sensors crafted and produced by Keynes Controls.
Submersible pH Sensor = The Intelligent Submersible pH Sensor by Keynes Controls, is a high performance submersible sensor that has been designed to simplify the acquisition of water quality measurement parameters into any platform that supports data logging operations using digital network communications. Read More...
Built-in Communication Options
The ARGES Nitrite Sensor supports SDI12, RS485 and MODBUS digital communications as standard enabling it to be directly connected to Data Logger for remote web based reporting, onto Wi-Fi and Local Area Networks using the RS485 option. The MODBUS and RS485 option are often used to connect sensors to a PLC Controller and Display Units,. The MODBUS protocol enables the sensors to be used directly by most SCADA applications software.
MODBUS Operations
ALL of the ARGES range of chemical sensors support MODBUS network operations The sensors act as a slave unit only and can communicate to suitable controllers and SCADA systems that support the MODBUS Protocol. The sensors support 16 and 32 bit registers. .
The ARGES sensors can be connected to a PC based system using the optional USB-485-Pro media converter. This device can power the chemical sensor and supports the correct timing protocols for data transmission for MODBUS and standard RS485 network communications
Multiparameter Housing
The ARGES Nitrite Sensor by Keynes Controls can be used as a stand-alone device or as a part of a multi-parameter solution. Keynes Controls currently manufacture 7 port and 3 port sensor housings. An optional submersible brush unit is available for cleaning the fluorometer optics and this can be fitted into any port within the housings..
Multiparameter Measurements
Any combination of ARGES sensors selective can be fitted into the multiparameter housing. All of the housings can be directly connected to data recorders, web based recording and display systems and any SCADA system supporting MODBUS.
Optional Accessories
The ARGES Nitrite Sensor by Keynes Controls is integrated into the free issue Keynes Controls Q-LOG software.
Our Q-LOG software runs on the widely recognised Windows Operating system, you have the ability to calibrate, adjust instrument network address, and effortlessly display measurements on a series of panel meters and charts. Conveniently store results in text based files for quick analysis in spreadsheets.
The optional USB media converters can be used to connect a multi-parameter instrument to a PC
The ARGES Nitrite Sensor by Keynes Controls is integrated into the Keynes Controls Q-LOG software.
Our Q-LOG software runs on the widely recognised Windows Operating system, you have the ability to calibrate, adjust instrument network address, and effortlessly display measurements on a series of panel meters and charts. Conveniently store results in text based files for quick analysis in spreadsheets.
