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Instructions for Use SS 20.60 

Page 13/16

 

8  Service information 

Maintenance 

The  sensor  tip  must  be  checked  regularly  for  contamination  and 
must  be  cleaned  when  required.  Contamination  of  the  sensor 
element may lead to a false measurement. It is recommended to 
check  it  once  a  year  and  more  frequently  if  it  is  heavily 
contaminated. 

 

Cleaning the sensor tip 

The  sensor  tip  can  be  cleaned  to  remove  dust/dirt  by  moving  it 
carefully  in  warm  water  containing  (a)  washing-up  liquid;  if 
necessary  a  very  soft  brush  can  be  used.  Before  putting  it  back 
into operation, wait until the sensor tip is completely dry. 

 

 

 

 

ATTENTION 

Do  not  use  strong  cleaners,  solvents,  brush  or 
other hard objects

 

Recalibration 

If  the  customer  has  made  no  other  provisions,  we  recommend 
repeating  the  calibration  at  a  12-month  interval.  To  do  so,  the 
sensor must be sent in to the manufacturer. 

 

Summary of Contents for SS 20.60

Page 1: ...SCHMIDT Flow Sensor SS 20 60 Instructions for Use ...

Page 2: ...ormation 4 4 Determination of the position of installation 5 5 Mounting instructions 8 6 Electrical connections 9 7 Startup 10 7 1 LED display 10 7 2 Error signaling 12 8 Service information 13 9 Declaration of conformity 15 Imprint Copyright 2003 SCHMIDT Technology GmbH All rights reserved Printed in the Federal Republic of Germany Version 300754 02B ...

Page 3: ...ity for a certain purpose and cannot be held liable for errors contained in these instructions for use or for accidental or sequential damage in connection with the delivery performance or use of this unit 2 Range of Applications The SCHMIDT flow sensor SS 20 60 is designed for stationary use in compressed air pipes air ducts or air shafts under atmospheric pressure conditions The sensor measures ...

Page 4: ...d tightening torque 20 Nm minimum 30 Nm maximum 3 In case of mechanical strain vibration the nut AF24 must be secured additionally e g using a commercially available screw lock 4 Make sure to close the safety chain before pressure is applied The chain lock must be hung up in a way to avoid sagging of the chain ATTENTION The maximum allowed positive operating pressure of 16 bar must not be exceeded...

Page 5: ...isturbances such as edges seams bends etc The design of the run out distance is also important since disturbances do not only act in the direction of the air flow but also lead to turbulence opposite to the flow direction run in distance L1 run out distance L2 D Figure 1 Sensor position in the pipe L total length of the measuring distance L1 length of the run in distance L2 length of the run out d...

Page 6: ...s toward the measuring area 15 x D 5 x D Expansion conduit expands toward the measuring area 15 x D 5 x D 90 bend or T junction 15 x D 5 x D Two 90 bends in one plane 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 This table lists the minimum values required in each case If the listed straight conduit l...

Page 7: ...e 7 16 Installation position The sensor should preferably be installed in horizontally positioned pipes ATTENTION Avoid installing the sensor in a pipe with downward flow This would considerably increase the lower measuring range limit ...

Page 8: ...ng the sensor in the pipe 2 Tighten the union nut AF24 until the arrow on the sensor housing corresponds to the direction of the pipe flow The angular deviation should not be greater than 3 referenced to the ideal position Otherwise the measurement accuracy may be affected You can check the set angular position by placing a bubble level on the stop face In case of wrong adjustment the through bolt...

Page 9: ...2 bn sw bl 24 VDC Signal GND ws Digital Figure 3 SS 20 60 connection assignment view of the plug pins at the sensor The cable supplied has the following color assignment ws white bn brown sw black bl blue The negative of the dc voltage GND is at the same time the reference potential for the analog signal ATTENTION Only operate the sensor in the defined range of operating voltage 24 VDC 20 Undervol...

Page 10: ...the signal outputs are specified on the rating plate see housing cover Note After applying the supply voltage the output signal will at first adopt a higher value and then level off at the correct measurement value after about 10 seconds 7 1 LED display The sensor has 4 LEDs indicating its current state ...

Page 11: ...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 high 11 Electronic temperature too low Table 2 Sensor state signaling LED off LED on green LED on orange LED flashes approx 2Hz red ...

Page 12: ...acturer for repair The other error states signaled by the LEDs are not indicated at the analog output LED signaling remains active until the cause of the error has been eliminated ATTENTION Causes of any error signaling have to be eliminated immediately A significant exceeding or falling below the permitted operating parameters can result in permanent damage to the sensor ATTENTION During error st...

Page 13: ...nated Cleaning the sensor tip The sensor tip can be cleaned to remove dust dirt by moving it carefully in warm water containing a washing up liquid if necessary a very soft brush can be used Before putting it back into operation wait until the sensor tip is completely dry ATTENTION Do not use strong cleaners solvents brush or other hard objects Recalibration If the customer has made no other provi...

Page 14: ...t the manufacturer In case of defects the parts must be sent in to the supplier for repair When the sensor is used in systems important for operation we recommend keeping a replacement sensor in stock Test certificates Upon request we shall prepare at a charge a factory calibration certificate traceable to national standards ...

Page 15: ...Instructions for Use SS 20 60 Page 15 16 9 Declaration of conformity ...

Page 16: ...Instructions for Use SS 20 60 Page 16 16 SCHMIDT Technology GmbH Feldbergstrasse 1 D 78112 St Georgen Phone 49 0 7724 899 0 Fax 49 0 7724 899 101 info schmidttechnology de www schmidttechnology de ...

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