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SCHMIDT

®

 Flow Sensor 

SS 20.600  

Instructions for Use

 

Summary of Contents for SS 20.600

Page 1: ...SCHMIDT Flow Sensor SS 20 600 Instructions for Use ...

Page 2: ...tion range 4 3 Mounting instructions 7 4 Electrical connection 20 5 Signaling 25 6 Commissioning 30 7 Information concerning operation 31 8 Service information 32 9 Dimensions 36 10 Technical data 37 11 Declarations of conformity 39 Imprint Copyright 2022 SCHMIDT Technology GmbH All rights reserved Version 535084 02D Subject to modifications ...

Page 3: ...ructions for use will forfeit any warranty and exclude any liability The unit is designed exclusively for the use described below refer to chapter 2 In particular it is not designed for direct or indirect protection of personal or machinery SCHMIDT Technology cannot give any warranty as to its suitability for a certain purpose and cannot be held liable for errors contained in these instructions fo...

Page 4: ...nsor head is immersed in water and operated under pres sure the sensor may be damaged irreversibly Using the sensor in flammable gases the regulations of ATEX guideline has to be applied see below The sensor variants for use in potentially explosive atmosphere ATEX and oxygen O2 are not combinable Version ATEX The ATEX version of the sensor is designed for use in explosive gas at mosphere of zone ...

Page 5: ...h an oxygen content of more than 21 or pure oxygen can lead to fires or explosions It is explicitly pointed out that the customer when opening the packaging assumes full responsibility for cleanliness of sensor and its accessories according to standard IEC TR 60877 1999 As a general rule it is essential to avoid contamination of those parts of the sensor that come into contact with oxygen Carefull...

Page 6: ...nsor head including its flow guiding chamber is made of stainless steel 1 4571 Only the sensor head is coated with Parylene see Figure 2 1 The coating covers the entire sen sor head including the sensor chip within the flow chamer up to just before the assembly gap that results from the press fitting of the head into the probe s tube The fitting zone inside the tube is sealed by two O rings made o...

Page 7: ...ansport or mount ing the protective cap should be placed on the sensor head Mounting method The sensor SS 20 600 can be mounted only by means of a compression fitting which supports the sensor tube and ensures positive clamping The compression fitting as well as a pressure protection kit is included in the scope of delivery Due to the variety of applications the compression fitting exhibits differ...

Page 8: ... Appropriate safety measures are installed to avoid unintended discard ing of the sensor due to overpressure For measurements in media with overpressure appropriate safety measures must be taken to prevent unintended discard ing of the sensor If other accessories than the delivered pressure protection kit or alterna tive mounting solutions are used the customer must ensure appropriate safety measu...

Page 9: ...eded by crosstalk of the medium temperature on the sensor housing Flow characteristics Local turbulences of the medium can cause distortion of measurement results Therefore appropriate mounting conditions must be guaranteed to ensure that the gas flow is supplied to the sensor in a laminar4 i e quiet and low in turbulence state The corresponding measures depend on the system properties pipe chambe...

Page 10: ... of the flow measurement and must be placed in the flow as advantageous as possible for example in the middle of the pipe Position the sensor head always at the most advantageous position for flow measurement The sensor chip The measurement direction is clearly defined by the measuring princi ple unidirectional The measuring direction is indicated by means of two arrows the first indication is loc...

Page 11: ...nfavourable installation conditions free convection may in crease the crosstalk between heater and temperature element on the sensor chip and therefore the lower detection limit Measurements in a downward flow downdraft flow see Figure 3 3 lead to considerably increased measuring val ues in the lower flow range The area concerned depends on the system pressure Correct measuring values are displaye...

Page 12: ... corresponding distances is defined by the inner diameter of the pipe because the flow abatement depends directly on the aspect ratio of measuring distance and diameter Therefore the required abatement distances are specified as a multiple of the pipe diameter D Besides the degree of turbulence generation by the corresponding dis turbing object plays an important role A slightly curved bend direct...

Page 13: ...L2 Light bend 90 10 x D 5 x D Reduction Expansion 90 bend T junction 15 x D 5 x D Two 90 bends in one plane 2 dimensional 20 x D 5 x D Two 90 bends with 3 dimensional change in direction 35 x D 5 x D Shut off valve 45 x D 5 x D Table 1 Run in and run out distances The profile factors specified in Table 2 may become void by the use of flow rectifiers ...

Page 14: ...109 8 219 7 659 0 988 5 1537 2416 0 797 82 5 88 9 3 1 153 4 306 8 920 3 1380 2147 3374 0 804 100 8 108 0 4 6 231 0 462 0 1385 2078 3233 5081 0 812 125 0 133 0 7 2 358 7 717 5 2152 3228 5022 7892 0 817 150 0 159 0 10 4 519 8 1039 3118 4677 7276 11434 0 829 206 5 219 1 20 0 999 5 1999 5997 8995 13993 21989 0 835 260 4 273 0 32 0 1600 3201 9605 14408 22412 35219 0 840 309 7 323 9 45 6 2278 4556 13668...

Page 15: ... Installation in systems with square cross section For most applications two limit cases can be distinguished with regard to flow conditions Quasi uniform flow field The lateral dimensions of the flow guiding system are approximately as large as its length in the flow direction and the flow velocity is small so that a stable trapezoidal9 speed profile of the flow is formed The width of the flow gr...

Page 16: ...5 is a hydraulic pipe diameter DH bR Width of rectangular channel hR Height of rectangular channel DH Hydraulic pipe diameter 𝐷𝐻 4 𝐴𝑅 𝑈𝑅 4 𝑏𝑅 ℎ𝑅 2 𝑏𝑅 ℎ𝑅 2 𝑏𝑅 ℎ𝑅 𝑏𝑅 ℎ𝑅 Figure 3 5 According to this the volume flow in a shaft is calculated as 𝐴𝐻 𝜋 4 𝐷𝐻 2 𝜋 4 2 𝑏𝑅 ℎ𝑅 𝑏𝑅 ℎ𝑅 2 𝜋 𝑏𝑅 ℎ𝑅 𝑏𝑅 ℎ𝑅 2 𝑤 𝑁 𝑃𝐹 𝑤𝑁 𝑉 𝑁 𝑤 𝑁 𝐴𝐻 𝑃𝐹 𝜋 𝑏𝑅 ℎ𝑅 𝑏𝑅 ℎ𝑅 2 𝑤𝑁 bR hR Width height of the square chamber m DH Hydraulic inner diamete...

Page 17: ...ngth mm Installation process Depressurize the system for measurements with overpressure media and mount the pressure protection kit Drill a mounting bore in a pipe wall Weld the pipe union with an internal thread G or R in the center above the mounting opening on the pipe Recommended length of the pipe union 15 40 mm Plug the holding bracket of the pressure protection chain into the thread of the ...

Page 18: ... with the direction of the pipe flow Check the set angular position carefully for example by placing a bub ble level on the aligning surface of the sensor enclosure The angular deviation should not be more than 3 with respect to the ideal measuring direction Otherwise the measurement accuracy may be affected In case of wrong adjustment the compression fitting has to be loosened and the alignment p...

Page 19: ...rl Material Brass nickel plated Polyamide PUR PP Halogen free11 Coupler socket With thread locking 524929 Threaded ring knurl Material Brass nickel plated Polyamide PUR PP Connection of wires Screwed 0 25 mm2 Clamp12 a 524916 b 524882 Internal thread G R Material a Steel black b Stainless steel 1 4571 Table 3 Accessories Informations about further accessories for mounting and display cis avail abl...

Page 20: ...White 2 UB Operating voltage 24 VDC 20 Brown 3 Analog TM Output signal Temperature of medium Auto U I Green 4 Analog wN Output signal Flow Auto U I Yellow 5 AGND Reference potential for analog outputs Gray 6 Pulse 2 Output signal Flow volume relay13 Pink 7 GND Operating voltage Ground Blue 8 Pulse 2 Output signal Flow volume relay13 Red Shield Electromechanical shielding Meshwork Table 4 The speci...

Page 21: ...are designed as high side driver with Auto U I feature and are short circuit protected against both rails of the operating voltage Use of only one analog output It is recommended to connect the same resistance value to both analog outputs even if only one of them is used For example if only the flow output is operated in current mode with a resistance value of a few ohms it is recommended to conne...

Page 22: ... wire resistances RW of the connection cable which can lead to measuring errors mass offset For voltage mode a measuring resistance of at least 10 kΩ is recommended The maximum load capacitance CL is 10 nF Short circuit mode In case of a short circuit against the positive rail of the supply voltage UB the signal output is switched off In case of a short circuit against the negative rail GND of the...

Page 23: ... driving of low impedance loads e g optocoupler relays etc with a maximum current consumption of approx IL max 100 mA This allows calculating the minimum permitted static load resistance RL min depending on the operating voltage UB 16 𝑅𝐿 𝑚𝑖𝑛 𝑈𝐵 3 𝑉 𝐼𝐿 𝑚𝑎𝑥 𝑈𝐵 3 𝑉 0 1 𝐴 Example In case of the maximum operating voltage of UB max 28 8 V the minimal load is RL min 258 Ω Here the excessive heating power...

Page 24: ...e can destroy the impulse output Wiring of impulse output 2 relay The output is realized by a semiconductor relay with the following technical characteristics Technology SSR PhotoMOS relay Maximum leakage current IOff max 2 µA Maximum resistance RON 16 Ω typ 8 Maximum switching current IS 50 mA Maximum switching voltage US 30 VDC 21 VAC eff Wiring Figure 4 4 The relay output is protected against s...

Page 25: ...D 2 LED 3 LED 4 1 Ready for operation flow 5 2 Flow 5 3 Flow 20 4 Flow 50 5 Flow 80 6 Flow 100 overflow 7 Sensor element defective 8 Operating voltage too low 9 Operating voltage too high 10 Electronic temperature too low 11 Electronic temperature too high 12 Medium temperature too low 13 Medium temperature too high Table 5 LED off LED on orange LED on green LED flashes19 red 18 Component with two...

Page 26: ...the load resistance such that a safe detection can be maintained 300 Ω for current mode and 10 kΩ for voltage mode To detect possible alternating load in an actual zero signal the elec tronics generates test pulses that correspond to an effective value of approx 1 mV However the latest measuring devices may trigger in response to such a pulse in DC voltage measuring mode and display short term mea...

Page 27: ...𝑤𝑁 𝑤𝑁 𝑚𝑎𝑥 10 𝑉 𝑈𝑂𝑢𝑡 𝑤𝑁 𝑤𝑁 𝑤𝑁 𝑚𝑎𝑥 16 𝑚𝐴 𝐼𝑂𝑢𝑡 𝑤𝑁 4 𝑚𝐴 Table 7 Representation specification for flow velocity measurement The measuring range of the medium temperature starts at the selected measuring range TMin and ends at 120 C see Table 8 Voltage mode U Current mode I 𝑇𝑀 120 𝐶 𝑇𝑀𝑖𝑛 10 𝑉 𝑈𝑂𝑢𝑡 𝑇𝑀 𝑇𝑀𝑖𝑛 𝑇𝑀 120 𝐶 𝑇𝑀𝑖𝑛 16 𝑚𝐴 𝐼𝑂𝑢𝑡 𝑇𝑀 4 𝑚𝐴 𝑇𝑀𝑖𝑛 Table 8 Representation specification for measurement of mediu...

Page 28: ...hes to error 0 V or 2 mA 21 The measuring function for the flow velocity is switched off its analog output also signals an error 0 V resp 2 mA o Medium temperature above 120 C TM is output in a linear way up to at least 130 C e g to enable over shooting of heating control The flow velocity is measured and dis played further on Above this critical limit flow measurement is switched off and the anal...

Page 29: ...ual output frequency the measur ing range wN max of the sensor and the inner pipe diameter D 𝑉 𝑁 𝑤𝑁 𝑃𝐹 𝐴𝐷 𝑤𝑁 𝑃𝐹 𝜋 4 𝐷2 𝑉𝑁 𝐼𝑚𝑝 𝑉 𝑁 𝑚𝑎𝑥 𝑓𝑚𝑎𝑥 When configured as a consumption meter pulses with a predefined pulse valency e g 1 m pulse are transmitted To do this the inner pipe diameter D must be specified when ordering Dmin 25 mm Exceeding the measuring range of the flow wN is also output linearly up t...

Page 30: ...rted correctly into the female cable connector o Tight fit of spigot nut on the cable connector at the sensor housing After switching on the operating voltage the sensor signals its initialization by switching all four LEDs sequentially to red orange and green If the sensor detects a problem during initialization it signals the problem according to Table 5 An extensive overview of possible errors ...

Page 31: ...ful chemical aggressive constituents23 are included Dust or non abrasive particles can be tolerated as long as they do not form any deposits on the sensor chip Deposits or other soiling must be detected during regular inspections and removed during cleaning because they can lead to distortion of the meas urement result see chapter 8 Service information Dirt or other deposits on the sensor head cau...

Page 32: ...as the interior of the chamber head can be cleaned carefully by using residue free drying alco hol e g isopropyl alcohol or soapy water with special cotton swabs Figure 8 1 Suitable cotton swabs with small cleaning pads Suitable for this purpose are cotton swabs which have small flattened and soft cotton pads example see Figure 8 1 The flat side of that pad should fit just between chamber wall and...

Page 33: ...age Possible causes Troubleshooting Problems with supply voltage UB No UB present UB has wrong polarity UB 15 V Sensor defective Plug in connector of cable screwed on correctly Supply voltage connected to control Supply voltage at sensor plug available cable break Sufficient power supply Send sensor in for repair No LED is lit All signal outputs at zero Start sequence is repeated continuously all ...

Page 34: ... signal voltage permanently at zero Error signaling Short circuit against A GND Eliminate errors Eliminate short circuit Table 9 Transport Shipment of the sensor Before transport or shipment of the sensor the delivered protective cap must be placed onto the sensor head Avoid contaminations or mechanical stress Calibration If the customer has made no other provisions we recommend repeating the cali...

Page 35: ...rtant for operation we recommend you to keep a replacement sensor in stock Test certificates and material certificates Every new sensor is accompanied by a certificate of compliance according to EN 10204 2 1 Material certificates are not available Upon request we shall prepare at a charge a factory calibration certifi cate traceable to national standards ...

Page 36: ...Instructions for Use SCHMIDT Flow Sensor SS 20 600 Page 36 9 Dimensions Compact sensor Figure 9 1 Remote sensor including wall mounting bracket Figure 9 2 ...

Page 37: ...v 0 4 o f v min 0 08 m s 24 only for air nitrogen oxygen Response time t90 wN 1 s jump of wN from 0 to 5 m s in air Temperature gradient wN 8 K min at wN 5 m s Recovery time constant 10 s temperature jump Δϑ 40 K at wN 5 m s Measuring accuracy25 TM 1 K 10 30 C 2 K remaining measuring range Operating temperature Sensor probe Standard 20 120 C O2 version 20 60 C ATEX version 40 120 C Electronics 20 ...

Page 38: ...gh side driver connected to supply voltage PNP without galvanic separation High level supply voltage 3 V Short circuit current limitation 100 mA Leakage current IOff 10 µA Semiconductor relay output galvanically separated Max 30 VDC 21 VAC eff 50 mA Connection Plug in connector M12 A coded 8 pin male screwed Maximum cable length Voltage signal 15 m current signal pulse 100 m Installation position ...

Page 39: ...ole responsibility that the product SCHMIDT Flow Sensor SS 20 600 Part No 524 600 is in compliance with the appropriate European guidelines and standards and UK statutory requirements and designated standards The corresponding declarations of conformity can be download from SCHMIDT homepage www schmidt sensors com www schmidttechnology de ...

Page 40: ...T Flow Sensor SS 20 600 Page 40 SCHMIDT Technology GmbH Feldbergstraße 1 78112 St Georgen Germany Phone 49 0 7724 899 0 Fax 49 0 7724 899 101 Email sensors schmidttechnology de URL www schmidt sensors com www schmitttechnology de ...

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