FMS EMGZ621A, Operating Manual, Page: 16 / 40

Operating Manual EMGZ621A
16
Mathematical method
If the material tension cannot be simulated, calibration has to be done by calculation. This way
of calibrating is less accurate because the exact angles are often unknown and the effective
mounting conditions, which usually deviate from the ideal, are not taken into account.
•
Offset adjustment is done as written under „Simulating method“.
•
The Gain value will be calculated by the following formula and then inputted in the
parameters
Gain A / Gain B (refer to „9.5 Description of the parameters EMGZ621A“).
fig. 10: Force vectors in the FMS force measuring bearing C431012e
Definition of symbols:
α
angle between vertical and measuring
web axis F
B
material tension
β
angle between vertical and F
M
F
G
roller weight
γ
wrap angle of material F
M
measuring force resulting from F
B
γ
1
entry angle of material F
Meff
effective measuring force
γ
2
exit angle of material
δ
Angle between measuring web axis and F
M
( )
2 2 / sin sin
1
⋅ ⋅
= =
γ δ
ckB GainFeedba ckA GainFeedba