The E7 is a very accurate and responsive automatic tension controller which is used to regulate unwind, rewind or intermediate web tension. It has a DC voltage output suitable for almost all standard electric brakes and clutches. A large meter on the front of the enclosure displays actual web tension which is measured by DFE tension transducers. The enclosure is industrial-duty steel with a hinged cover. All operator devices are mounted in an aluminum legend plate on the cover. If desired, the enclosure can be omitted and the E7 supplied with electronics panel connected to the legend plate with a wire harness. Construction of the E7 is modular. All electrical connections on the circuit cards are unpluggable terminal strips (except AC power). Identified test points on the cards make trouble-shooting easy.
The E7 is very easy to operate. Simply turn the tension setting knob until the meter indicates the tension desired. The controller will automatically maintain it regardless of changes in web speed or roll diameter. A soft start circuit prevents brake lock-up when starting with a slack web. Sample/Hold and multiply /divide circuits provide smooth operation during flying splices. Manual control is also provided in addition to automatic control. A tracking circuit provides bumpless switching between Auto and Manual.