KWS-100 COD Sensor
Applications
The COD sensor is Kacise's new generation of environmentally
friendly COD / TOC sensors. It does not require reagents, is
non-polluting, is more economical, and is more environmentally
friendly. The water volume is small, easy to install, and water
quality monitoring can be performed online. Automatically
compensates for turbidity disturbances and is equipped with an
automatic cleaning device that maintains excellent stability even
over long periods of time.
Feature
Digital sensor, RS-485 output, support MODBUS
No reagents, no pollution, more economical, more environmentally
friendly
Can measure SAC, COD, TOC and other parameters
Automatically compensates for turbidity interference for
outstanding test performance
Measuring principle
Many organic substances dissolved in water absorb ultraviolet
light. Therefore, by measuring the absorption of these organic
substances by ultraviolet light at a wavelength of 254 nm, the
total amount of organic pollutants in water can be measured. The
kacise COD series sensor uses two light sources, one 254nm
ultraviolet light and one 850nm infrared light, which can
automatically compensate the optical path attenuation and turbidity
effects, thus achieving more stable and reliable measurement
values.
Technical Specifications
| Range | 0~1500 mg/L |
| Resolution | 0.01mg/L COD |
| Ip Grade | IP68 |
| Material | POM and 316L |
| Operating Temperature | 5~45℃ |
| Output | RS485, Modbus |
| Power Supply | DC12V ±5%, current<50mA |
| Sensor Diameter | 54mm |
| Sensor Length | 310.5mm |
| Cable Length | Standard 10m |
| Calibration | Support one point and two-points calibration |
| Max. Pressure | 1 bar |
Dimension
Specific Technical Specifications
| Product | Measuring range | Application field |
| KWS100A(40mm gap) | SAC 0.1 to 50 1/m COD 0.15 to 75 mg/l equiv. KHP TOC 0.06 to 30 mg/l equiv KHP | Tap water treatment |
| KWS100B(8mm gap) | SAC 0.5 to 250 1/m COD 0.75 to 370 mg/l equiv. KHP TOC 0.3 to 150 mg/l equiv KHP | Sewage treatment plant outlet, natural waters |
| KWS100C(2mm gap) | SAC 1.5 to 700 1/m COD 2.5 to 1000 mg/l equiv. KHP TOC 0.9 to 410 mg/l equiv KHP | Industrial process control |
Calibration
1. KWS-100 COD sensor (see modbus user manual for details) provides
1-point or 2-point COD calibration option in mg / L. KHP (potassium
hydrogen phthalate, C8H5KO4), CAS # 877-24-7, as a commonly used
stain for environmental research, can be used for COD calibration.
The conversion formula for COD254nm and TOC254nm is as follows:
c (TOC) = 0.4705 * c (KHP)
c (COD) = 1.176 * c (KHP)
2, Preparation
2.1 Weigh 1.2754 g of KHP accurately into a 1000 mL flask. Use
distilled or deionized water and pour until the highest mark. This
solution contains 1500mg COD.
2.2 Put 100 mL of this solution into a 1000 mL volume flask, and
then fill it with distilled water or deionized water to the highest
mark. Shake to ensure that the COD content is 150 mg / L.
2.3 Store this concentrated standard solution in a black glass
bottle (step 2.1) and store it at low temperature to prevent
decomposition. . Diluted Standard Solution
(Step 2.2) Use within 24 hours after preparation.
3, Calibration (2-point calibration)
3.1 Restore user calibration data to default, K = 1, B = 0 (see
modbus documentation for details).
3.2 Place the sensor in pure water (distilled or deionized water)
and make sure that all light paths are immersed in water> 2cm
and free of air bubbles. Note: Do not use tap water. Then read the
COD value, such as COD = 0.2mg / L, and record it as X.
3.3. Place the sensor in a 150mg / L COD solution and repeat step
3.2 to record the value as Y.
3.4 Record K and B values as follows:
K = 150 / (Y-X), B =-KX
3.5 Write the K and B values to the sensor.
Warning: KHP is carcinogenic. Wear gloves when handling.
