Vishay G4-DT, Техническое руководство, Страница: 39 / 174

G4 Multi Channel Force Instrument
3-3
Web Tension Mode
A Function Block can be configured for web tension measuring by setting set-up
parameter ‘X:Web Tension Mode’ to On. In this case some of the force values will be
recalculated to a web tension value using the ‘X:Web Tension Factor’ as shown below.
Web Tension Value = Force Value / Web Tension Factor
If the Force Values are correctly calibrated in the desired measuring direction then the
‘Web Tension Factor’ shall be set to the length of the roller (machine width) to get
correct Web Tension values, e.g. N/m. In other cases the ‘Web Tension Factor’ must
be calculated based on calibration direction, web tension measuring direction, roller
length, etc.
The following table and figures explains the function and the values from a Function
Block in web tension mode.
A ‘(F)’ in the table below indicates a force value and a ‘(WT)’ a web tension value.
Value
1 Channel
Func. Block 2 Channel
Func. Block 4 Channel
Func. Block
Sum Input A (WT) Input (A+B) / 2 (WT) Input (A+B+C+D) / 2 (WT)
Difference - Input A-B (WT) Input (A+B) – (C+D) (WT)
Output 1 Input A (WT) Input A (WT) Input A+B (WT)
Output 2 Input A (F) Input B (WT) Input C+D (WT)
Output 3 - Input A (F) Input A (F)
Output 4 - Input B (F) Input B (F)
Output 5 - - Input C (F)
Output 6 - - Input D (F)
Output 7 - - Input A+B (F)
Output 8 - - Input C+D (F)
Sum
Input A
1 / WTF
Output 2
Output 1
WTF = Web Tension Factor
One Channel Function block, Web Tension mode
Sum
Input A
1 / WTF
Output 3
Output 1
Input B
1 / WTF
Output 2
Output 4
Difference
1/2
+
+
+
-
WTF = Web Tension Factor
Two Channel Function block, Web Tension mode