FMS CMGZ411, Руководство по эксплуатации

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Operating Manual CMGZ411/421
4
3 Description
3.1 Common
The CMGZ411/421 is a digital web tension controller. The electronic unit contains a microprocessor to handle all
calculations and communications, the highly accurate sensor power supply and the signal amplifier for the measuring
value. As operation interface it provides 4 keys, 4 LED’s and a 2x16 characters display in the front of the electronic
unit. All inputs are saved in an EEPROM. The electronic unit has no jumpers or trimmers to keep most accurate long-
time and temperature stability. There can be connected one or two force sensors to the electronic unit.
Strain gauge amplifier: The strain gauge amplifier provides the highly accurate 4V power supply. A highly accurate,
fixed difference amplifier rises the mV signal up to 10V. This signal will be fed to the A/D converter. The
microprocessor then does all application-specific calculations with the digitized measuring value (such as offset, gain,
low-pass filter). The tension feedback signal is available at the 0...10V analogue output.
Controller: The control unit compares the reference value with the measured feedback value and transmits the error to
the controller configurable as PI, PD or PID. The controller calculates the output signal according to the difference. The
output signal is provided as an analogue signal (0...10V / ±10V / 0...20mA / 4...20mA).
Interface: As standard, the electronic unit supports an RS232 interface. As an option, there is an additional board with
CAN-Bus interface available.
3.2 Special functions CMGZ411
Gain switching: For applications with different wrap angles, the gain factor can be changed easily using a digital input.
Correction input: For applications with continuously varying wrap angles (i.e. at winders/unwinders directly), the
CMGZ411 provides a 0..10V input for the continuous correction. The correction signal usually is obtained from a PLC
or from a potmeter that is mounted at the moving section of the machine. Correction can be set to linear or cosine
function.
Diameter calculation: In winder / unwinder applications, the controller is able to calculate the actual diameter.
Therefore it is necessary to get line speed information from a tacho roller or from a PLC. Line speed information is
given to the controller using a 10V input.
Taper function: Based on the diameter calculation, the CMGZ411 is able to reduce tension reference automatically
across the increasing diameter. Three different reduction curves (square, linear, square root) are available. The tension
then is reduced from given reference at center diameter to the desired reduction at the maximum winding diameter.
Note:
Only one of the features that use an analog input (Diameter, Correction input, analog reference) can be used at a time.
Special functions CMGZ421
Double channel measurment: The CMGZ421 calculates the tension reference values independently for the 2 bearings
of a measuring roller. Analogue outputs provide the feedback signals for channel A, channel B and channel A+B. The
controller uses the feedback signal A+B.
If the Difference between A and B exceeds a limit value, an error message occurs.
Gain switching: For applications with different wrap angles, the gain factor can be changed easily using a digital input.