The ARGES Potassium Sensor By Keynes Controls, is a Rugged solid-state 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. The instrument uses solid reference and potassium cell for long life and reliable results under poressure. No gells or reagents are used.
Each of the ARGES Potassium Sensor by Keynes Controls is suitable for direct connection to industry standard SDI12 Data Recorder, RS485 and MODBUS networks. The instruments can communicate directly across a MODBUS network and can be integrated into plant wide SCADA applications and to to many 3rd party PLC controllers.
ISOLATION
The sensor element of the Potassium Sensor is isolated to prevent any current flow between 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.
Measument Integrity
The ARGES Potassium Sensor sensor has the instrument serial number and latest calibration date built-in. The user can interogate the sensor for this information at any time. Any measurements taken by the sensor can be easily traced through the record structure.
Product Features
| TYPE | RANGE (Typical levels) |
| Solid state ISE sensor. | |
| Temperature range | 1 - 60 Deg C |
| Measurement range: | 0.5 to 39000 ppm - User selectable range |
| Potassium Resolution: | Five auto range scales: 0.4 - 39000 ppm. Temperature compensated readings |
| Potassium Accuracy: | 9% of reading |
| Operation |
Stand-alone / multiparameter solutions. |
| Sensor life: | Approximately 2 Years , depending on usage. |
| Long storage shelf life | Dry storage |
| SI Units - SDI12v1.4 | ppm, mg/l , mols/dm³ , Deg °C |
| Calibration Period | Re-calibrate before use - after 1 week deeployment - depending upon use. |
| pH | 1 - 9 |
| Interference IONS | Rb⁺ (2), Cs⁺ (0.4), NH₄⁺ (0.01), Na⁺ (0.0004), Ca²⁺ (0.0003), Mg²⁺ (0.0003), Li⁺ (0.0001) |
Calibration Summary
The ARGES Potassium Sensor By Keynes Controls can be used within SONDE multi-parameter housing, or as a stand-alone sensor. The ARGES Potassium Sensor should calibrated before use for optimum results.
Keynes Controls offer a calibration kit for The ARGES Potassium Sensor and this is available from the online store.
The ARGES Potassium Sensor is typically calibrated at 2 points. A high level concentration and low level concentration. Keynes controls typically use 103.6 ppm and 20.7 ppm calibration solutions. No special apparatus is required for the sensor calibration. A simple user calibration function is built into the free QLOG software for this sensor.
For optimum results calibrate the sensor just above and below the range for which the sensor will be used.
When measuring concentrations of metals and minerals in water:
1 milligram per liter (mg/L) = 1 part per million (ppm)
0.000016 mols / dm³ = 1 ppm for dissolved potassium
Note mols / dm³ is used for high concentration measurements
Storage and Handling
When not in use the ARGES Potassium Sensor By Keynes Controls can be stored dry be left in storage for long periods of time for convienient use.
Rehydrate before deployment using distilled water.
Storage temperature range : 2 - 60 Degrees Celsius.
Application Uses
- Wastewater Treatment
- Agricultural Runoff Monitoring
- Measuring Potash Mining Water Contamination
- Drink Water Quality Monitoring
- Effluent Monitoring
- Aeration tasks
Product Specifications
| POTASSIUM SENSOR | ENVIRONMENTAL CHARACTERISTICS | |||
| Range | 0.1 to 39000 ppm - auto scaling (User set range) | Temp Range: 0 to 60 Deg C | ||
| Resolution | 0.01 ppm | Ambient Range: 0 - 50 Deg C | ||
| Accuracy | 9% of reading | Water Temp : -2 to 60 Deg C | ||
| Maximum Depth: 20 m | ||||
| Electrodes: | Reference Electrode / Potassium cell - Solid state- Potentiometric | |||
| Material: | PVC / Stainless Steel | PHYSICAL DIMENSIONS | ||
| Interference ION: | Rb⁺ (2), Cs⁺ , NH₄⁺ (0.01), Na⁺ (0.0004), Ca²⁺ (0.0003), Mg²⁺ (0.0003), Li⁺ (0.0001) | Length x Diameter: 22 x 220 mm | ||
| Weight: 97 g | ||||
| Settling Time |
|
Maximum Depth : 20 m | ||
| User Range | Miniumum ppm / Maxiumum ppm | |||
| Drift | 20.27 millivolts/day | Built-in Network Types: | ||
| Excitation | Galvanic | SDI12 / RS485 / MODBUS | ||
| Housing | 316 Stainless Steel | |||
| Sensor Connector | Gold Plated | Power Requirement | ||
| Voltage Range: 10-15 V DC | ||||
| Data Output | ppm, mg/l , mols/dm³ , Deg °C (User Assigned) | Standby Current: 1 mA Typical | ||
| Temperature Comp | ppm, mg/l , mols/dm³ | Reading: 12 mA Typical |
Please Note: The ARGES Potassium sensor is pre-calibrated at the factory.
Rehydrate the sensor head if stored dry before use.
Supported Commands
Most Used Commands - SDI12
Full list of user assigned parameters are shown on the User Configuration page of the QLOG software.
| Description | Command | 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 |
| Set Output Variables | XCSTR0 | Sets the parameter order for measurements sent from the sensor - factory set BCDM |
| Read Serial Number | aXSN! | Instrument Response a+Serial-number |
| Calibration Date | aXCD! | Instrument Response a+date |
| First Calibration point (ppm) - | XCA0 | as read from the sensor - calibration mode |
| - | - | - |
| User Assigned Parameters | ||
| First Calibration point (ppm) | First calibration solution concentration in ppm | |
| First calibration point (millivolts) | Raw Sensor reading at 1st calibration point | |
| Second Calibration point (ppm) | Second calibration solution concentration in ppm - eg 100 ppm | |
| Second calibration point (mV) | Raw Sensor reading at 2nd calibration point | |
| SDI12 V1.14 Units | Automatically assigned - ppm, mg/l , mols/dm³ , Deg °C | |
| where mols/dm³ useful for high concentration readings | ||
| Calibration Temperature | Temperature in Deg C at which the calibration was undertaken | |
| Temperature Correction | millivolt / Deg C (-2.04 typically) |
The ARGES Potassium sensor parameters can be adjusted for additional SI Units such as mg/l instead of ppm along with the order in which the parameters are returned across a network.
Commonly used with: Ammonia, pH, Nitrate & Temperature Sensors.
The ARGES Potassium Sensor by Keynes Controls monitors the levels of Potassium in water. The ARGES Potassium Sensor readings can be affected by changes in temperature and salinity. This sensor is frequently paired with the Nitrate, pH, Ammonia sensor and other temperature sensors crafted and produced by Keynes Controls.
ARGES Nitrate Sensor : Submersible Nitrate sensor is a solid state device that operates in exactly the same as the potassium sensor. Commonly used with the Potassium sensor when monitoring for river pollution.
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 Potassium Sensor has the SDI12, RS485 and MODBUS digital communications built-in 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 and will operate directly with many 3rd party SCADA applications.
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 Housings / SONDE
The ARGES Ammonium Sensor by Keynes Controls can be used as a stand-alone device or as a part of a multiparameter solution. Keynes Controls currently manufacture 7 port and 3 port sensor housings. An optional submersible brush unit is available for cleaning the sensor underwater.
Multiparameter Measurements
Any combination of ARGES sensors selective can be fitted into the multiparameter housing
Accessories
Keynes Controls manufactures a range of accessories that can be used to connect the ARGES range of sensors to a Windows computer system and enable the sensors to be used in Laboratory applications, multi-parameter instruments and calibration operations.
The optional USB media converters can be used to connect a multi-parameter instrument to a PC
The ARGES Potassium Sensor is integrated into the Keynes Controls Q-LOG software.
The ARGES Potassium 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.