Amer Technical Information TI 312e00 Solids Content Sensor SAH-T/E Solids Content Sensor for Average Concentrations Using the Light Abso

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1 Technical Information TI 312e00 Solids Content Sensor SAH-T/E Solids Content Sensor for Average Concentrations Using the Light Absorption Method The 7510 sensor is used for optical solid matter content measurement in turbid water for up to 40 g solid matter/l. Applications Solid matter content measurement in suspensions Separation zone detection in sedimentation processes Industrial quality control Return activated sludge Waste activated sludge Features and benefits Reliable concentration measurement using optical measurement process Four-beam pulsed light method for compensation of sensor soiling and ageing of optical components Stainless steel sensor body No mechanically moving parts Measured value preprocessing in sensor resulting in low signal transmission sensitivity ISO 9001

2 7110 MTF-FG 7110 MTF Measuring system Examples for complete measuring systems 7110 MTF or 7301 GWT with 7510 SAH-E Measuring system 7110 MTF or 7301 GWT with 7510 SAH-T The complete measuring system consists of: Turbidity transmitter 7110 MTF or 7301 GWT Turbidity sensor 7510 SAH-T/E Sensor 7510 SAH-E Sensor 7510 SAH-T Sensor cable Sensor cable 7110 MTF / 7301 GWT US61-11.CDR 7110 MTF / 7301 GWT US61-10.CDR 2

3 Measuring principle Calibration lieft: Principle of measured light diffusion S = Transmitter E = Receiver right: Principle of measured light attenuation analogue to Lambert- Beer s law I 0 = Intensity of transmitted light I A = Intensity of absorbed light I T = Intensity of light transmitted I S = Intensity of scattered light E = Extinction coefficient C = Concentration D = Optical path length Four-beam pulsed light method This method is based on two light sources and two photoreceivers. Long-life LEDs ( at least 20,000 operation hours) are used as monochromatic light sources. To eliminate interference from extraneous light sources, the LEDs are pulsed at a rate of several khz. Two measuring signals are detected at the two photoreceivers with every light pulse. The four measuring signals are compared logarithmically with each other and converted into a ratio. This compensates for detector soiling and the ageing of optical modules. S 1 E 1 S 2 Each sensor is subjected to a careful calibration at the factory. One customer calibration can also be saved. For the calibration of solids content measurement, such as sludge, refer to the concentration determined by a reference method (dry substance). E 2 UC-T09.CDR Light absorption method This measuring method is based on the Lambert-Beer law. Turbidity is measured by light attenuation. The LEDs on the sensor send a directed light beam to the photoreceivers. The intensity of the beam is attenuated by the solid matter particles in the medium. The photoreceivers measure the absoprtion signal and convert it into a frequency signal. The frequency signals are assigned to corresponding turbidity units and solid matter concentrations, and appear in the display. I 0 ECD I = I e lg I 0 = ECD T 0 I A D I T I T I S US61-15.CDR 3

4 Dimensions Dimensions left: Immersion type 7510 SAH-T right: Installation type 7510 SAH-E 146 / G1 38 US61-01.CDR US61-02.CDR 4

5 7110 MTF 7110 MTF Installation Installation example for 7510 SAH sensors Immersion type left: Tank installation 7510 SAH-T with immersion tube right: Channel installation with basin mounting and immersion tube US61-04.CDR Note: We recommend the use of an immersion tube with 180 thread for the 7510 SAH-T immersion type. US61-06.CDR Installing the sensor in pipelines or close to a wall can lead to backscattering and therefore to signal increase. 5

6 Installation Accessories Installation example of 7510 SAH sensor Installation version Tube installation with ball valve built-in assembly (Accessories) Flow direction Ball valve built-in assembly for sensor extension under process conditions, DN 40 with security locking Material: stainless steel SS 316Ti, O-rings made of Viton Order No.: Sensor fixing bracket for basin mounting Material: stainless steel SS 316Ti, Order No.: Sensor rinsing tool for SAH-T Order No.: rotatable Installation angle Required mounting clearance US61-19.CDR Immersion tube 1 m Material: stainless steel SS 316Ti Order No Immersion tube 2 m Material: stainless steel SS 316Ti Order No Immersion tube 3 m Material: stainless steel SS 316Ti Order No.:

7 Technical data General specifications Manufacturer ISI Europa Ordering information Product designation Mechanical data Dimensions (l x ) Installation type Immersion type Weight Installation type Immersion type Solids content sensor 7510 SAH-T/E mm 146 x 38mm approx. 3kg approx. 1kg Material Sensor body Stainless steel SS 316 Ti Sight glass 7510 SAH-T with frequency output SAH-T with analog output SAH-E with frequency output SAH-E with analog output SAH-E-SP with frequency output and integrated rinse nozzle 7515 SAH-E-SP with analog output and integrated rinse nozzle POM O-rings Viton Turbidity measurement Measuring principle Light absorption method Optical components Measuring light Measuring range Accuracy Reference Light source: 2 LEDs, Detector: 2 photodiodes Infrared light at 880nm (absorption maximum) g solid matter/l, dependent on sludge type < 1% of measuring range end value using four-beam pulsed light method Factory calibration SiO 2 Cable lengths T version 13m E version 1m + 10m extension cable Operating conditions Operating temperature C Operating pressure Ingress protection IP 68 max. 6 bar Supplementary documentation Technical Information 7110 MTF Order No.: Technical Information 7301 GWT Order No.: Subject to modifications. 7 Subject to modifications.

8 ISI Europa P. O. Box D Gerlingen Tel Fax TI 312e00/08.01 Printed in Germany / CV5 / DT (Nr )