Tension control system

(1)     The menu function enables storage and reading of 4 types of operation data.

(2)     The optional memory cassette enables reading of operation data and writing of data in the other STC-858A tension controller.

(3)     The controller has a weak excitation function for powder clutch / powder brake.

This function will improve the torque rising operation in low-speed operation mode or during the initial start-up of machine.

Automatic tension control system, STC-858A tension controller

STC858A tension controller is a full digital tension controller with high precision and multi-function which to match up tension detector to form a closed-loop tension controller system an then receives the signal from LS series tension detector after intelligent PID operation processing internally, regulating implementing structure and to auto matically control the tension of the long material at the unwinder, feed reel, and winder.

STC858A tension controller uses a new graphical LCD display which Chinese and English display clearer and then generates a control voltage of 0 to 24V DC to control the powder clutch/brake and the hysteresis clutch/brake, or generates the torque command voltage of 0 to 10V to send to the servo amplifier.

Features

• Gsimple raphical LCD display 128x96 with the capability of dispaly Chines and English characters, it has programming and easy to operate.
• Multi-function select: automatic tension controller with taper tension controlling function.
• Using high precision D/A converter, and the output precision reach to 0.1%, and which makes the tension controller with high precision, more stable and reliable.
• Can drive the powder clutch/brake directly, also can control frequency converters, servo motor and electro-pneumatic converter.
• Can receive the single-way or double-wayinput signal from tension detector and with automatic zero set and automatic calibration.
• With  Dual axis switching and speed up/slow down controlling function¡£
• With password settings function which can avoid changing set parameter when it operated incorrectly.
• With memory cassette which can backup various parameter.
• With human interface design which is very easy to operation.

Tension Controllers

Tension and Torque Controllers automatically compensate for changes in roll diameter, speed and other process variables.

What is Web Tension Control ?

Web tension control can be defined as the maintenance of a set amount of web tension (pull or force) for a material being processed. Often measured in oz, lbs, grams, kg, or newtons ¡ª proper tension must be maintained to prevent stretching, wrinkling, breaking or inconsistent registration of material during printing or converting processes.

Web tension control improves uniformity in coating applications and material lamination while decreasing the incidence of rewind defects such as crushed cores, starring and telescoping. When web tension is under control it can enable processes to run at higher speeds while reducing scrap, delivering a rapid return on investment that boosts producers' long term profitability.

Where is web tension control most commonly used?

Web tension control is most commonly used in three zones: Unwind (infeed), Intermediate (process), and Rewind (take up).

In the unwind zone, infeed roll hold-back torque is often controlled by an electric or pneumatic brake. The web strain or tension resulting from this torque is regulated by a closed-loop controller to prevent web drooping, stretching or wrap-up incidents ahead of transiting to the intermediate zone.

Proper maintenance of intermediate zone tension is often critical to ensuring the quality of coating, laminating, curing, treating or slitting processes. This zone is typically controlled by a set of driven nip rollers which dictate line speed to the entire system. This speed reference is matched in the unwind and rewind by virtue of having to accelerate or decelerate in order to maintain a desired tension set point.

Proper tension in the rewind zone ensures under or over-tight rolls and their associated defects are prevented. Rewind zone torque is often controlled by the motor drives of center or surface winders. Implementing progressive taper tension techniques during winding is an effective way to ensure finished rolls maintain spring tension stability and do not experience material shift and core deformation during handling and storage.

From process start to finish, it's clear that reliable web tension control is the key to ensuring maximum system efficiency and quality of finished products.

Typical tension control solutions incorporate:

• Sunrise Automatic tension controller such as the LTC-858A,LTC-858A

• Sunrise Tension sensor such as LS series or LC series tension sensor

• Sunrise A Pneumatic Brake, Magnetic Particle Brake, Clutch