Classifications

• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01T—SPARK GAPS; OVERVOLTAGE ARRESTERS USING SPARK GAPS; SPARKING PLUGS; CORONA DEVICES; GENERATING IONS TO BE INTRODUCED INTO NON-ENCLOSED GASES
  • H01T1/00—Details of spark gaps
  • H01T1/14—Means structurally associated with spark gap for protecting it against overload or for disconnecting it in case of failure
• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01C—RESISTORS
  • H01C7/00—Non-adjustable resistors formed as one or more layers or coatings; Non-adjustable resistors made from powdered conducting material or powdered semi-conducting material with or without insulating material
  • H01C7/10—Non-adjustable resistors formed as one or more layers or coatings; Non-adjustable resistors made from powdered conducting material or powdered semi-conducting material with or without insulating material voltage responsive, i.e. varistors
  • H01C7/12—Overvoltage protection resistors

Definitions

• the invention relates to a surge arrester with a gas-filled housing in which there are cylindrical electrodes which are tapered in the shape of a truncated cone and are spaced apart from one another by a tubular insulating body and which are thicker-walled in the area of the active surfaces than the conical side walls in the area of the transition to the insulating body on the inner wall thereof
• Line of electrically conductive material extends as an ignition line in the direction from one electrode to the other electrode, the surge arrester being able to be installed in a metallic sleeve serving as a holder with a movable basket surrounding the arrester.
• Such a surge arrester is known from DE-OS 28 28 650.
• the collector has copper electrodes with a strong waffle that contains an electrode activation mass.
• the Keraaikisoier body encloses the electrodes, which have a small distance.
• On the ceramic insulating body several graphite stripes are applied to the.
• the graphite streaks have no contact with the electrodes at both ends and are therefore referred to as center streaks.
• center streaks In this way, isolation gaps are created in a switched-off back room, which also with 500 A wave during the life cycle 10 / 1000 ⁇ s can not be vaporized by sputtering.
• the effectiveness of center ignition bars on the response surge voltage is, however, less than that of ignition bars connected to an electrode, so that the permissible response voltage limit is exceeded earlier during lifetime operation with center ignition bars.
• gas-filled surge arresters are increasingly being used to protect telephone systems against overvoltages. Versions with a short-circuit mechanism are used for the station protection and central building protection. A sleeve with a movable basket tightly encloses the surge arrester. Gas-filled surge arresters with good electrical properties are already known from DE-OS 28 28 650 mentioned at the beginning.
• the present invention has for its object to take advantage of the electrical influence of the concentrically enclosing socket to create gas-filled surge arresters with even further improved life-time properties.
• the socket is at ground potential and concentrically tightly surrounds the arrester, and / or the ignition line is electrically conductively connected to the electrode designed as a wire or pin electrode and in Low-evaporation rear space of the other electrode designed as a perforated electrode ends, the two electrodes being arranged in such a way that an almost equally large distance is formed between the electrodes and between the perforated electrode and the ignition line.
• the two electrodes are pre-cast made of copper and on the inner wall of the insulating body four ignition lines made of graphite are attached.
• a soft solder pill is provided between the base of the socket and the perforated electrode. This measure further increases the operational safety of the operator. If the conductor is overloaded, the soft solder pill melts and the holder is then pressed against the electrode by means of a spring, thus causing a safe short circuit with the counterelectrode via the holder. Surge arresters equipped in this way are therefore also referred to as arresters with fall-safe behavior.
• the present invention has the following advantages.
• the DC response voltage (slow voltage rise) is determined by the electrode gap.
• the surge voltage of the arrester outside the socket has a polarity effect. If there is cathode potential at the ignition screed above the electrode, the arrester has lower response surge voltage values than in the opposite direction. Abieiter within the socket have low pickup voltage values in both polarities, since the socket acts as an additional ignition aid. The low surge voltage values are retained during the life test.
• an electrode activation compound consisting of magnesia oxide and Ni powder, with a grain size between 1 to 40 ⁇ m, a switching frequency in the life test with 500 A, wave 10 / 1000 ⁇ s> 1000 is achieved due to a stable DC response voltage and good insulation.
• the surge arrester 1 shown in the figure consists of a gas-filled housing, preferably with a noble gas filling.
• frustoconical cylindrical electrodes 3, 4 are inserted, which are thick-walled in the area of the active surfaces than the conical side walls in the area of the transition to the insulating body 5.
• the surge arrester 1 is in a serving as a socket 2 metallic Inserted sleeve from a movable basket concentrically enclosing the drain 1, which is slit on the side and has a central opening at the bottom.
• the socket 2 is guided in a metallic cylinder 11. When using output 1, this version 2 is at ⁇ rd potential.
• the ignition lines 6 are electrically conductively connected to the electrode 3 designed as a wire or pin electrode and end in the low-vaporization rear space of the other electrode 4 designed as a perforated electrode. Both electrodes 3, 4 are dimensioned such that the distance between the electrodes 3, 4 and is formed between the hole electrode 4 and the ignition lines 6.
• a deep waffle 7 is provided in which an elec electrode activation mass 8 is anchored.
• the electrode activation composition preferably consists of magnesium oxide and nickel powder with a grain size between 1 to 40 / um.
• a soft solder pill 9 is provided between the perforated electrode 4 and the bottom of the holder 2 and melts when the conductor 1 is overloaded.
• the socket 2 is pressed against the hole electrode 4 by a spring force, the direction of which is indicated by the arrow 12, and a safe short circuit is brought about with the wire electrode 3 (counter electrode), namely via the side wall of the socket 2, which is pressed against the wire contact.

Landscapes

• Engineering & Computer Science (AREA)
• Microelectronics & Electronic Packaging (AREA)
• Physics & Mathematics (AREA)
• Electromagnetism (AREA)
• Thermistors And Varistors (AREA)
• Gas-Insulated Switchgears (AREA)
• Emergency Protection Circuit Devices (AREA)

Applications Claiming Priority (2)

Publications (1)

Family

ID=6116700

Family Applications (1)

Country Status (6)

Families Citing this family (9)

Family Cites Families (13)

• 1980
  • 1980-11-13 DE DE19803042847 patent/DE3042847A1/de not_active Ceased
• 1981
  • 1981-11-11 JP JP56503641A patent/JPH0127553B2/ja not_active Expired
  • 1981-11-11 EP EP81903118A patent/EP0064528A1/de not_active Ceased
  • 1981-11-11 WO PCT/DE1981/000197 patent/WO1982001792A1/en not_active Application Discontinuation
  • 1981-11-12 CA CA000389927A patent/CA1189137A/en not_active Expired
• 1985
  • 1985-04-23 US US06/726,187 patent/US4583147A/en not_active Expired - Fee Related

Non-Patent Citations (1)

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