FMS CMGZ411, Руководство по эксплуатации

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Operating Manual CMGZ411/421
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If the reaction of the control loop is not fast enough, Parameter „PID configuration“ can be set to PID to
add a derivative control component. The adjustment of the derivative component D starts with small
values. Increase as long as the loop remains stable.
If the reference value can’t be reached, there is a static error (eg. no or too small I component). In a steady
state with no static error, the reference can be reached and also maintained.
To judge the adjustment of the control loop, an oscilloscope can be very helpful. The oscilloscope not only
shows whether the control loop operates in a stable manner, but also whether there is a static error.
10.3 Enable controller
After switching the CMGZ411/421 on, the controller is locked. The output signal is zero if a drive is used,
regardless of tension reference and feedback. If a brake is used, the output signal will be the start torque
defined in parameter „start speed“.
By using the digital input "controller enabled" or the corresponding serial interface command, the controller
starts to work.
Control loop with a drive
The behaviour of the controller after it is enabled is determined by the parameters
″
Start speed
″
and
″
Start
limit
″
. These two parameters ensure an easy starting phase: If there is slack material in the machine and the
controller controls a drive, it would accelerate suddenly to achieve the reference tension. As soon as the
material is stretched, the drive can not decelerate fast enough, and the material can be stretched excessively
so that tearing results. To avoid this, the controller starts with only a small output signal given by parameter
″
Start speed
″
until a certain tension value (given by parameter
″
Start limit“) is reached. After that, the
controller switches very smoothly (without the output signal jumping from one value to another) to tension
control mode, and the digital output „Controller ok“ is activated.
With configuring the parameter
″
Start limit“ to 0, this behaviour can be suppressed and the controller begins
to operate immediately. Although this is possible, it is advisable to use a value greater than zero, because this
starting procedure takes only fractions of a second if there is no slack material.
If a 1-Q drive is used as an unwinder, the starting procedure is inactive, as the drive is only able to turn in the
unwinding direction.
If a 1-Q drive is used as a winder, a speed value (start speed) and the corresponding tension force (start limit)
can be given as provided.
If a 4-Q drive is used, the complete starting procedure can be followed. The values must be set depending on
the machine and the material that is used.
Control loop with a brake
Using a brake, the controller starts to work immediately after enabling the controller. That means the output
value is made depending of the control error (reference - feedback), and the digital output „Controller ok“ is
activated.
If the Controller is used with a brake, the slow starting process must be controlled by another drive in the
machine, because the brake is not able to drive the material. Parameter
″
Start speed
″
is adjusted so that the
brake is able to hold a certain torque but not too high. (Caution! Frictional grip of brake after standstill).
Parameter
″
Start limit
″
is not used because the controller starts to work immediately after enabling the
controller.
10.4 Controller lock
To stop control operating, reset the digital input „controller enabled“ or activate the corresponding serial
interface command, depending on how you started the controller.
If no brake is used and the parameter
″
Synchronisation-stop
″
is set to „yes“, the controller don’t stops
immediately but continues to control until the output signal is zero. Then, the dig. output „Controller ok“ will
be reset. If parameter
″
Synchronisation-stop
″
is set to „no“, the output value will be zero immediately.
If a brake is used, the output value will be reduced to the start torque (start speed). If the start torque is
reached, the dig. output „Controller ok“ will be reset.