EoW July 2011

technology news

Winding resistance meter with one-time connection system

The Tettex 2293 is the result of extensive research and years of experience testing transformers. It incorporates a fast and highly advanced procedure to measure winding resistance. A simple one-time-connection system together with the simultaneous winding magnetisation method reduces measuring time. The simultaneous winding magnetisation (SWM) method ensures fast and reliable measurements even on large power transformers with delta windings on the low voltage side, where stable measurements can seldom be reached using traditional winding resistance measurement instruments. In addition, the new demagnetisation function eliminates the magnetic remanence in the core after the application of a DC voltage. The full graphical interface with a 7" touch screen guides the operator through the test procedure. The unit visualises each test cycle and displays the results graphically or in list format. Haefely has also introduced new cable test terminations and a water processing unit. Cable test termination systems are used for high voltage testing of power cables.

▲ ▲ Haefely’s water-filled cable test terminations and water processing unit

“ ACID-FREE PROCESS FOR STEEL ROD CLEANING & SURFACE PREPARATION” “New Way to Draw Steel Wire in the 21 st Century”

Before high voltage (AC or impulse) can be applied, the power cable needs to be pre-pared and terminated in a special way in order to control the electrical field distribution along the ends.

The

Haefely

water-filled

Cable Terminations CTT and Water Processing Unit WPU offer a suitable connection for these tasks. The new generation of CTTs are optimised for AC routine testing and completed by a modern, easy to use water processing unit. The CTT range covers rated AC voltages from 100kV to 800kV, for diameters of maximum 115, 130 or 165mm across outer semiconducting layer. Test

DCCD process features: • Eliminates acid, borax and precoatings • Zero energy consumption • Direct drawing from bare rod with no speed limitation, for H/C and L/C • New Lubricant Viscosity Control provides exceptionally adherent coating • Adjustable lubricant residual • Zero lubricant waste • Recommended for severe drawing applications (spring, rope, bead, CO 2 welding, PC strand, plating quality) • H/C wire drawn at 18 m/s (3600 ft/min) • Up to 8 times longer die life • Exiting wire temp. 45°C (113°F) • Greatly improved wire ductility

Advantages short tubes for easy handling and less cable waste; rugged design; hydraulic jacking system (manual or automatic); service friendly design; pneumatic valves that ensure partial discharge free operation; and a modern, user-friendly touch screen interface. Haefely Test AG – Switzerland Fax : +41 61 373 49 12 ▲ ▲ Tettex 2293 include

DECALUB 31, avenue de Condé 77500 CHELLES, FRANCE Fax: +33 1 60 20 20 21 E-mail: info@decalub.com Website: www.decalub.com

Website : www.haefely.com

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EuroWire – July 2011