SI21001A

SI21001A - Monolithic circuit for symmetrical protection of telecommunication systems with thermally interconnected PTC element and varistor

Info

Publication number: SI21001A
Application number: SI200200205A
Authority: SI
Inventors: Janez Alič; Igor Orel
Original assignee: Alfa & Omega, D.O.O.
Priority date: 2002-08-26
Filing date: 2002-08-26
Publication date: 2003-02-28

Abstract

Subject of the invention is a monolithic circuit for symmetrical protection of telecommunication systems with thermally interconnected PTC element and varistor, representing a component of secondary protection of digital line inputs in telecommunication systems. The monolithic circuit for symmetrical protection of telecommunication systems with thermally interconnected PTC element and varistor according to the invention offers the possibility of providing surge protection with a very short time between the circuit breaking and active current at a relatively small basic resistivity of the PTC element so that all elements are thermocoupled into the monoliths PTCa + varistor and PTCb + varistor.

Description

Predmet izuma je monolitno vezje za simetrično zaščito 10 telekomunikacijskih sistemov s termično sklopljenim PTC elementom in varistorjem in predstavlja sestavni del sekundarne zaščite analognih ali digitalnih linijskih vhodov telekomunikacijskih sistemov. Izum spada v razred H 02 h 3/08 mednarodne patentne klasifikacije.The subject of the invention is a monolithic circuit for symmetrical protection of 10 telecommunication systems with thermally coupled PTC element and varistor and is an integral part of the secondary protection of analog or digital line inputs of telecommunication systems. The invention belongs to the class H 02 h 3/08 of the international patent classification.

Tehnični problem, ki ga predložena konstrukcija monolitnega vezja 15 uspešno rešuje je izvedba zaščitnega vezja, ki bo omogočalo čim krajši čas med odklopnim in delovnim tokom pri serijski upornosti zaščitnega modula in kratek čas odklopa pri temperaturi okolice, kot ot določajo tehnične zahteve za določen telekomunikacijski sitem ali napravo.The technical problem that the proposed construction of monolithic circuit 15 successfully solves is the implementation of a protective circuit that will allow the shortest possible time between the tripping and operating current at the series resistance of the protection module and the short tripping time at ambient temperature, as determined by the technical requirements for a particular telecommunication system. or the device.

Poznana so zaščitna vezja za tokovno zaščito telekomunikacijskih 20 naprav, za katere je značilno, da delujejo v vsaki žili samostojno, sestavne elemente takih sistemov pa se predstavljajo induktivni elementi, upori, PTC upori in žične varovalke. Slabost takih zaščitnih vezij je sorazmerno dolg čas med odklopnim in delovnim tokom, ne zagotavljajo sočasnega odklopa a in b žile, kar lahko zaradi pretvorbe simetričnega prenapetostnega udara v asimetrični udar povzroči dodatne poškodbe varovanega vezja.Known circuits for the current protection of telecommunications 20 devices, which are characterized by operating in each vein independently, and the components of such systems are inductive elements, resistors, PTC resistors and wire fuses. The disadvantage of such protection circuits is the relatively long time between the disconnect and the operating current, they do not guarantee simultaneous disconnection of the a and b veins, which can lead to additional damage to the protected circuit due to the conversion of a symmetric surge into an asymmetric shock.

Monolitno vezje za simetrično zaščito telekomunikacijskih sistemov s termično sklopljenim PTC elementom in varistorjem po izumu, omogoča izvedbo tokovne zaščite s kratkim časom med odklopnim in delovnim tokom pri relativno majhni osnovni upornosti PTC elementa tako, da so elementi termosklopljeni v monolita PTCa + varistor a in PTCb + varistorMonolithic circuit for symmetrical protection of telecommunication systems with thermally coupled PTC element and varistor according to the invention, enables the implementation of short circuit protection current and operating current protection at relatively low basic resistance of the PTC element such that the elements are thermally coupled into PTCa + varistor a and PTCb monoliths + varistor

b.b.

Izum bomo podrobneje obrazložili na osnovi izvedbenega primera in slik, od katerih kaže:The invention will be explained in more detail on the basis of an embodiment and figures, of which:

slika 1 električno shemo tokovne zaščite;Figure 1 is a schematic diagram of the current protection;

slika 2 shematski pogled na monolit PTCa + varistor a in PTCb + is varistor b.Fig. 2 is a schematic view of the monolith PTCa + varistor a and PTCb + is varistor b.

Vhodni sponki a,n in b,_n vezja po izumu sta priključeni na plinski odvodnik 1, in vsaka preko monolita PTC + varistor na izhodni sponki a_outin bout· Tako je sponka a,_n preko monolita PTCa + varistor a priključena na sponko a_out, sponka b_in pa preko elementa PTCb + varistor b na sponko bout- Za učinkovito delovanje vezja po izumu morata oba monolita PTCa + varistor a in PTCb + varistor b imeti zelo podobni osnovni upornosti ter dober sotek upornosti po vsem temperaturnem območju. Vsi elementi so termično sklopljeni v skupni monolit, ki v znatni meri določa minimalni odklopni tok monolitnega sestava.The input terminals a, n and b, _{n of the} circuit of the invention are connected to a gas arrester 1, and each via the PTC + varistor monolith on the output terminal a _out and bout · Thus terminal a, _n via the PTCa + varistor a monolith is connected to terminal a _ou t, terminal b _and through the element PTCb + varistor b to terminal bout- For the effective operation of the circuit according to the invention, both monoliths PTCa + varistor a and PTCb + varistor b must have very similar basic resistances and a good resistance across the entire temperature range. All elements are thermally coupled into a common monolith, which substantially determines the minimum disconnect current of the monolithic composition.

V posameznih primerih lahko varistor v sestavi zamenja plinski odvodnik. Monolita prevzameta vlogo sekundarne zaščite, medtem ko je 5 pri močnejših tokovnih udarih, ki jih ponavadi spremlja tudi prenapetostni udar, višji od 200 V, primarna zaščita izvedena s pomočjo plinskega odvodnika.In some cases, the varistor in the composition may be replaced by a gas arrester. Monoliths take on the role of secondary protection, while 5 in the case of more powerful electric shocks, which is usually accompanied by an overvoltage impact higher than 200 V, the primary protection is performed by means of a gas arrester.

Claims

PATENT APPLICATIONS

1.

io 2.

3.

Monolithic circuit for symmetrical protection of telecommunication systems with thermally coupled PTC element and varistor, characterized in that one or more PTC elements are thermally coupled with one or more varistors into a monolithic circuit.

Monolithic circuit for symmetrical protection of telecommunication systems with thermally coupled PTC element and varistor according to claim 1, characterized in that the elements are thermally coupled into PTCa + varistor a and PTCb + varistor b of the monolith.

Monolithic circuit for symmetric protection of telecommunication systems with thermally coupled PTC element and varistor according to claims 1 and 2, characterized in that the varistor in the monolithic circuit is replaced by a gas arrester.