Specifications

Chapter 3: General Considerations
Compression versus Tension Load Cells
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General Considerations
Compression versus
Tension Load Cells
There are two basic types of load cells for use in weigh modules:
Compression load cells are designed so that a tank or other structure can be mounted
on top of the weigh module. The weight being measured compresses the load cell.
Tension load cells are designed so that a tank or other structure can hang from the
weigh module. The weight being measured stretches the load cell, creating tension.
Whether you use compression or tension weigh modules often depends on the specific
application. Table 3-1 provides an overview of how general design factors affect the
choice of weigh modules.
Design Factor Compression Load Cells Tension Load Cells
Floor Space Requires enough floor space to accommodate
tank size. Might require buffer space around
tank.
Requires no floor space and can be suspended
to allow movement beneath tank.
Structural Restrictions Weak floors might require additional
construction or a special installation to
accommodate weight of filled tank.
Weak overhead supports/ceilings might require
additional construction or special installation to
accommodate weight of filled tank.
Weight Limit Generally unlimited. To ensure accurate load
distribution, there should not be more than eight
vessel supports.
Structural considerations might limit suspension
system capacity. With adequate support,
suspension systems can safely support as
much as 40,000 lb.
Load Cell Alignment Designs may vary and must consider floor
deflection, available support beams, and tank
size, shape, and condition.
Cell alignment will not vary significantly
because tension rods and other support
equipment tend to accommodate most
deflections.
Table 3-1: Comparison of Compression and Tension Load Cells