FMS EMGZ621A, Operating Manual, Page: 5 / 40

Operating Manual EMGZ621A
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4 System Description
fig. 1: Basic structure of the EMGZ621A Tension Measuring Amplifier E621A001e
4.1 Functional Description
The EMGZ621A is a double channel strain gauge amplifier for a single measuring point. The
material tension can be measured on both sides of the measuring roller independently.
The two force sensors of the measuring point measure the tension force in the material and
transmit the measuring values as mV signals to the electronic unit EMGZ621A. The electronic
unit amplifies the mV signals depending on configuration. The resulting feedback values are
shown in the display in [N] (lbs if required). In addition, the feedback values are provided at
the analogue outputs and various interfaces and can be evaluated by analog instruments, a
PLC or equivalent devices.
4.2 Force Sensors
The force sensors are based on the flexion beam principle. The flexion is measured by strain
gauges and transmitted to the electronic unit as mV signal. Due to the Wheatstone wiring of
the strain gauges, the measured value is depending also to the power supply. So, the force
sensors are supplied from the electronic unit by a very accurate power supply.