Principal Of Servo Measurement; Principle Of Measurement - Honeywell 954 SmartServo FlexLine Installation Manual

3. PRINCIPAL OF SERVO MEASUREMENT

Principle of Measurement

Figure 4 Principle of Measurement
Part No: 4417341 Revision 10
The principle is based on detection of variations in the buoyancy of a displacer. The
displacer is suspended from a strong, flexible measuring wire which is stored on a
precisely grooved measuring drum.
The shaft of the drum is connected to the stepper motor via a magnetic coupling.
The apparent weight of the displacer is measured by a force transducer. The actual output
of the force transducer is compared with a desired value for the apparent weight of the
displacer. If a discrepancy exists between measured and desired value, an advanced
software control module adjusts the position of the stepper motor.
Installation Manual
954 SmartServo FlexLine
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