Surface Strain Transmitter, Type 9238B...
Page 2 9238B_002-542e-02.23
Content
1.Introduction ................................................................................................................................... 4
2.Important notes.............................................................................................................................. 5
2.1For your safety ..................................................................................................................... 5
2.2Unpacking............................................................................................................................ 6
2.3Notes on using the transmitter ............................................................................................. 6
2.4Hints on using this instruction manual.................................................................................. 6
3.General description........................................................................................................................ 7
3.1What is strain? ..................................................................................................................... 7
3.1.1NormalsStrain – shear strain .................................................................................... 7
3.2What is the purpose of a strain transmitter?......................................................................... 8
3.3Design and principle of operation of strain transmitter Type 9238B... .................................. 9
3.3.1Design..................................................................................................................... 9
3.3.2Measurement principle .......................................................................................... 10
3.3.3Integral fully-digital charge amplifier ..................................................................... 10
3.4Factory calibration of transmitter........................................................................................ 11
4.Installation and commissioning ................................................................................................... 13
4.1Important instructions ........................................................................................................ 13
4.2Choosing measuring point.................................................................................................. 13
4.2.1Surface materials ................................................................................................... 14
4.3Allowing for thermal effects ............................................................................................... 15
4.3.1Self-heating........................................................................................................... 16
4.4Machining mounting surface.............................................................................................. 16
4.5Mounting........................................................................................................................... 18
4.5.1Mounting strain transmitter................................................................................... 18
4.6Connecting strain transmitter Type 9238B... ...................................................................... 19
4.6.1Notes on cable laying ............................................................................................ 19
4.6.2Connecting strain transmitter Type 9238B............................................................. 20
4.6.3Cable concept ....................................................................................................... 22
4.7Commissioning................................................................................................................... 23
4.7.1Simplest form of measurement – relative............................................................... 23
4.7.2Simplest form of measurement – strain.................................................................. 24
4.7.3Range switching .................................................................................................... 25
4.7.4Indirect force measurement................................................................................... 26
5.Calibration and maintenance ....................................................................................................... 27
5.1In-Situ calibration of surface strain transmitter Type 9238B................................................ 27
5.1.1Working point calibration by peak value comparison ............................................ 27
5.1.1.1Test system requirements....................................................................... 28
5.1.1.2Reference sensor installation .................................................................. 28
5.1.1.3Load application..................................................................................... 29
5.1.1.4Calibration process worksheet................................................................ 30
