ESK relay
The ESK relay , called precious metal quick-switch contact relay or precious metal quick-contact relay, is a special type of telecommunication relay .
Layout and function
The Siemens ESK relay came onto the market in 1957 with ESK technology (Edelmetall-Schnellrelais-Koppelfeld), initially for private private branch exchanges with the construction stages Bw57 and from 1960 with Bw60. Compared to the flat-panel telecommunications relays customary at the time, it was not only characterized by a greatly reduced switching time, but also by a smaller design and the option of arranging it in one- and two-dimensional arrays.
Thanks to a new design, the mass moved by the magnetic field of the coil was significantly reduced. Contact spring and armature have been combined into one element, the "contact armature ". The contact anchor, which is made of an iron-nickel alloy and has a mass of 0.3 grams, can switch the circuit within one to two milliseconds. The precious metal contacts are made of a palladium alloy and at that time had a comparatively high level of operational reliability with little maintenance and a long service life.
The ESK relay has two windings, the response coil and the hold coil. Five relays each are assembled to form a relay strip. These strips can be connected to multiples by means of a special shaping of the connection lugs with bare wire (a multiple connects the contacts of the same type of use). Frames with ESK relays could therefore be efficiently wired using programmable machines.
operation area
Central controls and entire coupling fields could be implemented using ESK relays . This enabled the electromechanical dialers to be replaced, which in addition to increasing the performance and reducing the size of telephone systems and exchanges also significantly reduced the noise of these systems. In public switching technology, for. B. in Austria introduces entire switching centers with ESK technology (e.g. 48ESK-A3). However, the relay was used by the Deutsche Bundespost (DBP) in public switching technology only in long-distance dialing technology (from system 62) as a relay search selector. Otherwise, the ESK relay in Germany was only used in private branch exchanges (e.g. ESK 400E). However, it became more widespread in foreign exchanges.
Series for this were z. B. ESK 10.000E, CP24 and CP44.
With the spread of digital semiconductor-based switching technology , the ESK relays quickly lost their importance.
literature
- Rudolf Kaiser: The ESK relay . Siemens AG, Berlin a. a. 1972, series of publications: Programmierte Unterweisung No. 48, ISBN 3-8009-4048-5 .
- Rudolf A. Storch: Introduction to telephone technology . Siemens & Halske AG, Berlin / Munich 1960 and 1961