Principle Of Measurement - ABB PFTL 101 User Manual

Pressductor PillowBlock Load Cells, Horizontal Measuring PFTL 101, User Manual
1 Introduction
1.4.3

Principle of Measurement

The load cell only measures force in the direction F . The measurement force may be positive or
R
negative. The load cell is normally installed under the roll bearings. When there is a web/strip in
tension over the roll, the tension (T) gives rise to two force components, one in the direction of
measurement of the load cell (F ) and one at right angles (F ).
R V
W
The measuring force depends on the relationship between the tension (T) and the wrap angle
a
formed by the web/strip around the measuring roll.
p
an
Wrap angle
T
F
R
T
F
V
Figure 2. Measuring roll with Force Vectors
8 3BSE009965R0401 en Rev E