Pressductor Pillowblock Load Cells Vertical Measuring PFCL 201 User manual

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Description

General

The load cell is machined from a single piece of stainless steel. The sensors are machined directly in the piece of steel and are positioned so that they are sensitive to force in the direction of meas urement and insensitive in other directions.

The load cell is mounted on a base with four screws, and the bearing housing is mounted on top of the load cell with four screws.

Every load cell comes calibrated and temperature compensated.

The load cells PFCL 201C/201CE/201CD are available in four measurement ranges, all variants have the same external dimensions.

The load cell PFCL 201C is equipped with a connector for the pluggable connection cable. The load cell PFCL 201CE has a fixed connection cable with protective hose. The load cell PFCL 201CD is provided with an acid-proof cable gland with a fixed PTFE- insulated connection cable.

Definitions

Nominal load

Nominal load, Fnom, is the maximum load in the measurement direction for which the load cell is dimensioned to measure within the specified accuracy class. The load cell is calibrated up to Fnom.

Sensitivity

Sensitivity is defined as the difference in output values between nominal load and zero load.  

Accuracy and Accuracy Class

Accuracy class is defined as the maximum deviation, and is expressed as a percentage of the sen sitivity at nominal load. This includes linearity deviation, hysteresis and repeatability error.

Linearity Deviation

Linearity deviation is the maximum deviation from a straight line drawn between the output values at zero load and nominal load. Linearity deviation is related to the sensitivity.

Hysteresis

Hysteresis is the maximum difference in the output signal at the same load during a cycle from zero load to nominal load and back to zero load, related to the sensitivity at nominal load. The hysteresis of a Pressductor transducer is proportional to the load cycle.  

Repeatability error

Repeatability error is defined as the maximum deviation between repeated readings under identical conditions. It is expressed as a percentage of the sensitivity at nominal load.

Compensated temperature range

The temperature drifts of the load cell have been compensated for in certain temperature ranges. That is the temperature range within which the specified permitted temperature drifts (i.e. zero point and sensitivity drifts) of the load cell are maintained.

Working temperature range

Working temperature range is the temperature range within which the load cell can operate within a specified accuracy. The maximum permitted temperature drifts (i.e. zero point and sensitivity drifts) of the load cell are not necessarily maintained in the whole working temperature range.

Storage temperature range

Storage temperature range is the temperature range within which the load cell can be stored.

Zero point drift with temperature

Zero point drift is defined as the signal change with temperature, related to the sensitivity, when there is zero load on the load cell.

Sensitivity drift with temperature

Sensitivity drift is defined as the signal change with temperature at nominal load, related to the sen sitivity, excluding the zero point drift.  

Compression

Compression is the total reduction in the height of the load cell when the load is increased from zero to the nominal value.

Measuring principle of the sensor

The measuring principle of the sensor is based on the Pressductor®  technology and the fact that the permeability of a magnetic material changes under mechanical stress.

The sensor is a membrane machined in the load cell. Primary and secondary windings are wound through four holes in the load cell so that they cross at right angles.