Area Compensation
been selected on the Recorder Panel. Determine the full
scale stress reading as follows:
Set the mantissa of the area compensation to 7.50, that
is, normalize the base number of the specimen area to a
value between 1.000 and 9.999. A 100-lb capacity load
cell with the % RANGE set at 10% has a full scale load
range of 10 lb. Substituting these values into the equa-
tion for Full Scale Stress:
If the % RANGE were changed to 20 (L.R. = 20) in the
above example, the Full Scale Stress would be 2000 psi.
This would overload the load cell (refer to Section
A.7.3).
Limitations Due To Load Cell Capacity
The maximum allowable stress within the capacity of a
load cell is determined by:
where: L.C. = Load Cell maximum capacity and A =
cross-sectional area of specimen.
For example, for a 100-lb load cell, and an Area = 0.075
in
Thus, to determine the highest % RANGE to use that
will not exceed the maximum allowable stress (S
use the equation:
A-12
7.50 x 10 lb
= 1000 psi
2
0.0750 in
Maximum Allowable Stress =
2
, the maximum allowable stress would be 1333 psi.
M10-94400-1
L.C.
A
),
max