ABB PFTL 101 - Principle of Measurement

1.4.3 Principle of Measurement
The load cell only measures force in the direction F
R
. The measurement force may be positive or
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
R
) and one at right angles (F
V
).
The measuring force depends on the relationship between the tension (T) and the wrap angle
formed by the web/strip around the measuring roll.
T
T
F
R
F
V
W
a
p
an
Wrap angle
Figure 2. Measuring roll with Force Vectors
Pressductor PillowBlock Load Cells, Horizontal Measuring PFTL 101, User Manual
1 Introduction
8 3BSE009965R0401 en Rev E