Erhardt+Leimer GmbH - Web tension controllers

Web tension controller DC 60/61

Digital web tension controller with different software packages for different actuators such as

Electric drives for unwinders and rewinder
Electric drives for transport drives
Electric and pneumatic brakes for unwinders
Mechanical variable drives and superimposed gear drives for transport drives

E+L Database Details

Control structure for unwinder with motorized drive

Two load sensors measure the web tension actual value of the running web. This is compared to the web tension target value and transferred as system deviation to the PID controller. The PID controller forms the speed correction signal

± delta v which is then added to the web speed signal v-web target. The v-web target corresponds to the v-web target of the main drive.

For unwinders the superimposed speed target value is divided by the actual batch diameter. The result is a superimposed speed target value for the speed-controlled unwinder.

Diameter calculator or connection for diameter sensor
Speed target value for unwinder
Winder characteristics F=f (D)

E+L Database Details

Control structure for winder with motorized drive

Two load sensors measure the web tension actual value of the running web. This is compared to the web tension target value and transferred as system deviation to the PID controller. The PID controller forms the speed correction signal

± delta v which is then added to the web speed signal v-web target. The v-web target corresponds to the v-web target of the main drive.

For unwinders the superimposed speed target value is divided by the actual batch diameter. The result is a superimposed speed target value for the speed-controlled unwinder.

Diameter calculator or connection for diameter sensor
Speed target value for winder
Winder characteristics F=f (D)

E+L Database Details

Control structure for motorized transport drive

Two load sensors measure the web tension actual value of the running web. This is compared to the web tension target value and transferred as system deviation to the PID controller. The PID controller forms the speed correction signal

± delta which is then added to the web speed signal. This signal is transmitted to the following drive.

Speed target value for transport drive

E+L Database Details

Control structure for unwinder with pneumatic brake

Two load sensors measure the web tension actual value of the running web. This is compared to the web tension target value and transferred as system deviation to the PID controller. The PID controller forms positioning signal for the following U/P converer The converter supplies a proportional positioning signal at the output to trigger a pneumatic brake.

Diameter calculator or connection for diameter sensor
Mass moment of inertia for quick stop
Brake caliper rotation
Moment target value for unwinder

E+L Database Details

Control structure for unwinder with electric brake

Two load sensors measure the web tension actual value of the running web. This is compared to the web tension target value and transferred as system deviation to the PID controller. The PID controller forms positioning signal for the following U/I converer The converter supplies a proportional positioning signal at the output to trigger an electric brake.

Moment target value for unwinder

E+L Database Details

Control structure for transport drive with variable positioning gear

Two load sensors measure the web tension actual value of the running web. This is compared to the web tension target value and transferred as system deviation to the three-position controller. Besides the analog speed target value two binary outputs for right and left run are available as positioning signals .The two binary outputs are used for contactor controls.

Three-position controller with adjustable window width and hysteresis
Optionally with analog speed target value for frequency converters

E+L Database Details

Control structure for transport drive with superimposed gear

Two load sensors measure the web tension actual value of the running web. This is compared to the web tension target value and transferred as system deviation to the tweb tension controller.

E+L Database Details