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Definition of Terms and Symbols

4,659 bytes removed, 10:36, 14 December 2022
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|The incremental electrical resistance generated by the constriction of the currents paths in the touching area (a-spot)
|-
|FremdschichtwiderstandFilm resistance
|R<sub>f</sub>
|[Ω]
|Wird durch eine Fremdschicht hervorgerufenGenerated by a foreign matter layer, die z.B. durch Reaktion der Kontaktoberfläche mit der Umgebungsatmosphäre entstehtwhich for ex. is formed by a reaction of the contact material surface with the surrounding atmosphere (Fremdschicht ist eine Substanz auf der Kontaktoberfläche, die sich in ihren Eigenschaften von dem für das Kontaktstück gewählten Werkstoff unterscheideta surface film is a substance on the contact surface with different properties than those of the actual contact material)
|-
|DurchgangswiderstandPath resistance
|R<sub>d</sub>
|[Ω]
|Wird bestimmt zwischen Bezugspunkten, vorzugsweise den Anschlussstellen, die frei gewählt werden können, jedoch angegeben werden müssenthe total electrical resistance between reference points (usually the device terminals) which can be freely chosen but must be defined. Er setzt sich zusammen aus dem Bahnwiderstand It is the sum of the conductor resistance R<sub>b</sub> der Kontaktteile und dem Kontaktwiderstand and the contact resistance R<sub>k</sub>
|-
|KontaktkraftContact Force
|F<sub>k</sub>
|[N]
|Die Kraft, die zwei Kontaktstücke im geschlossenen Zustand aufeinander ausübenThe force that is exerted between the two contact parts in the closed position
|-
|Contour area
|a
|[m]
|Radius der kreisförmigen wirksamen Kontaktflächeof the circular effective contact area
|-
|ElastizitätsmodulElastic modulus
|E
|[MPa]
|Materialkennwert aus der Werkstofftechnik, der bei Material characteristic value from materials engineering that describes the proportional relationship between stress and strain during the deformation of a solid body in the case of linear-elastischem Verhalten den proportionalen Zusammenhang zwischen Spannung und Dehnung bei der Verformung eines festen Körpers beschreibtelastic behavior
|-
|Härte Hardness (Brinell oder or Vickers)
|H
|
|Der mechanische Widerstand, den ein Werkstoff der mechanischen Eindringung eines anderen Körpers entgegensetztThe mechanical resistance that a material offers to the mechanical penetration of another body
|-
|StromstärkeCurrent
|I
|[A]
|Die elektrische Stromstärke gibt an, wie viel elektrische Ladung sich pro Sekunde durch einen Leiter bewegtThe electric current strength indicates how much electric charge moves through a conductor per second
|-
|Anzahl der wirksamen EinzelkontaktflächenNumber of effective individual contact areas
|N
|
|
|-
|Elektrischer WiderstandElectrical resistance
|R
|[Ω]
|Der elektrische Widerstand ist in der Elektrotechnik ein Maß dafürIn electrical engineering, welche elektrische Spannung erforderlich ist, um eine bestimmte elektrische Stromstärke durch einen elektrischen Leiter electrical resistance is a measure of the electrical voltage required to allow a certain electrical current to flow through an electrical conductor (Bauelementcomponent, Stromkreiscircuit) fließen zu lassen
|-
|Radius Kontaktflächecontact area
|r
|[m]
|
|-
|BahnwiderstandPath resistance|R<sub>bd</sub>
|[Ω]
|Der elektrische Widerstand eines Halbleiterkristalls im p- bzwThe total electrical resistance between reference points (usually the device terminals) which can be freely chosen but must be defined. n-dotierten Gebiet im Gegensatz zum Widerstand R<sub>Ü</sub> im Bereich der ÜbergangszoneIt is the sum of the conductor resistance Rb and the contact resistance Rk
|-
|Abstand der wirksamen Einzelkontaktflächen zwischen Distance of the effective single contact areas between i und and j
|sij
|[m]
|
|-
|Maximale KontakttemperaturMaximum contact temperature
|T<sub>Kmax</sub>
|[K]
|
|-
|SpannungVoltage
|U
|[V]
|Je größer die elektrische Spannung istThe greater the electrical voltage, desto mehr Ladung kann transportiert werden und dadurch steigt auch die elektrische Stromstärkethe more charge can be transported and thus the electrical current strength, i.e. the amount of charge, also die Ladungsmengeincreases.
|-
|KontaktspannungContact Voltage
|U<sub>K</sub>
|[V]
|Die bei Berührung zweier unterschiedlicher Substanzen entstehende elektrische SpannungThe electrical voltage created when two different substances come into contact. Die Ursache hierfür sind letztlich die unterschiedlichen Elektronenniveaus This is ultimately caused by the different electron levels in den Materialienthe materials
|-
|VolumenVolume
|V
|[m<sup>3</sup>]
|Das Volumen ist der räumliche Inhalt eines geometrischen KörpersThe volume is the spatial content of a geometric body
|-
|Spezifischer WiderstandSpecific resistance
|[Ω*m]
|Das Volumen ist der räumliche Inhalt eines geometrischen KörpersThe resistivity (Rho) is defined as the resistance of a conductor of 1 m length and 1 qmm cross-section (A) at a temperature of 20 degrees Celsius
|-
|AbhebekraftLifting Force
|F<sub>A</sub>
|[N]
|
|-
|AbriebFrictional wear
|
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|Der mechanisch bedingte Stoffverlust an KontaktstückenThe loss of material caused by mechanical wear between contact parts
|-
|PrellenBounce
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|
|Eine ein- oder mehrmalige Unterbrechung der Kontaktgabe während eines Schaltvorganges, hervorgerufen durch wechselweise Umwandlung von potentieller in kinetische EnergieThe single or multiple interruption of conduction between contact parts during the make operation caused by alternating transformation of kinetic to potential energy
|-
|KontaktverschleißContact Wear
|
|
|Umfasst alle Veränderungen der KontaktoberflächeIncludes all changes on a contact surface. Es ist zu unterscheiden zwischen elektrischem und mechanischem VerschleißMechanical and electrical wear must be distinguished
|-
|MaterialwanderungMaterial transfer
|
|
|Die bei Schaltvorgängen auftretende Übertragung von Kontaktmaterial von einem Kontaktstück auf das andereThe transfer of contact material from one contact part to the other. Sie tritt hauptsächlich in Gleichstromkreisen aufIt occurs mainly during switching of DC loads. Die Wanderungsrichtung ist dabei abhängig von den Lastkreisparametern und den verwendeten KontaktwerkstoffenThe direction of the transfer depends on the load circuit properties and the contact materials used
|-
|AbbrandArc erosion
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|Der Stoffverlust an die Umgebung der Kontaktstelle, der infolge Lichtbogeneinwirkung entstehtThe loss of material into the surrounding of the contact spot which is generated by electrical arcing. Er tritt sowohl beim Ein- als auch beim Ausschalten aufIt occurs during contact make as well as break operations
|-
|VerschweißenContact welding
|
|
|Tritt auf, wenn infolge hoher Strombelastung schmelzflüssige Berührungsflächen der Kontaktstücke aufeinandertreffenOccurs when melt-liquefied touching areas of the contact parts come in contact with each other. The melting occurs during high current carrying through these areas. Bei einschaltenden Kontaktstücken können PrelllichtbögenDuring make operations this occurs through bounce arcs, bei geschlossenen Kontaktstücken ein zu hoher Kontaktwiderstand oder dynamisches Abheben der Kontaktstücke infolge hoher Kurzschlussströme Ursache für das Verschweißen der Kontaktstücke seinon closed contacts a too high contact resistance or dynamic separation of the contacts due to high short circuit currents can cause the welding of the contacts. Das Verschweißen führt dann zu einem Geräteausfall, wenn die Schweißverbindung nicht durch gerätespezifische Öffnungskräfte wieder getrennt werden kannThe welding then may cause a device failure if the device specific opening forces cannot break the weld connection
|-
|LichtbogenwanderungArc movement
|
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|Tritt auf, wenn beim Ausschaltvorgang ein ausreichend hohes Magnetfeld vorhanden ist, das eine Kraft auf den Lichtbogen ausübt, die ihn von der Entstehungsstelle z.B. in eine Löschkammer ablenktHappens when during the break operation a sufficiently high magnetic field is generated which exerts a force on the electrical arc which is then moved from the originating spot towards an arc chute (or arc splitting plates)
|-
|Lichtbogenlöschung Arc extinguishing
|
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|Bedeutet den Strom zu Null werden zu lassen und die Lichtbogenstrecke vom leitenden in den nichtleitenden Zustand überzuführenMeans the process of letting the current go to zero and transferring the arcing gap from a conducting to the non-conducting stage. Die angewandten Löschprinzipien hängen hauptsächlich von StromartSelecting the most effective extinguishing measures depend mostly on the current characteristics, Stromstärke und Netzspannung abthe current value and the circuit voltage
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|Wiederverfestigung einer SchaltstreckeRecovery
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|Nennt man bei öffnenden Kontaktstücken den Vorgang, bei dem das elektrisch leitende Plasma des Lichtbogens nach dem Stromnulldurchgang seine Leitfähigkeit verliertof an arc gap during contact opening is defined as the process of the electrically conducting plasma of an arc losing its electrical conductivity after reaching current-zero
|-
|}
</figtable>
*'''Electrical contact''' <br />is a property which is generated through the touching of two electrically conducting surfaces.
 
*'''Contact part''' <br />is a metallic component which is designed to create or interrupt an electrical contact (is frequently replaced by the term “contact” if it is clearly understandable that a physical piece or item is meant).
 
*'''Contact area''' <br />is the whole area on a contact part that may be used for contacting.
 
*'''Apparent contact area A<sub>s</sub>''' <br />is the part of the contact area on contact parts that can make physical contact during the touching of two contacts.
 
*'''Load bearing contact area A<sub>t</sub>''' <br />is the part of the apparent contact area which is affected by the contact force. It is the sum of all microscopic actual touching points.
 
*'''Effective contact area A<sub>w</sub>''' <br />is the part of the load bearing contact area through which current is flowing and therefore the sum of all current carrying touching areas (a-spots), A<sub>w</sub> < A<sub>t</sub> < A<sub>s</sub>.
 
*'''Contour area A<sub>n</sub>''' <br />is the contiguous area which includes all effective a-spots, A<sub>w</sub> < A<sub>n</sub> < A<sub>s</sub> ; A<sub>n</sub> ≠ A<sub>t</sub>.
 
*'''Contact resistance R<sub>k</sub>''' <br />is composed of the constriction resistance and the film resistance.
 
*'''Constriction resistance R<sub>e</sub>''' <br />is the incremental electrical resistance generated by the constriction of the currents paths in the touching area (a-spot).
 
*'''Film resistance R<sub>f</sub>''' <br />is generated by a foreign matter layer, which for ex. is formed by a reaction of the contact material surface with the surrounding atmosphere (a surface film is a substance on the contact surface with different properties than those of the actual contact material).
 
*'''Path resistance R<sub>d</sub>''' <br />is the total electrical resistance between reference points (usually the device terminals) which can be freely chosen but must be defined. It is the sum of the conductor resistance R<sub>b</sub> and the contact resistance R<sub>k</sub>.
 
*'''Contact force F<sub>k</sub>''' <br />is the force that is exerted between the two contact parts in the closed position.
 
*'''Frictional wear''' <br />is the loss of material caused by mechanical wear between contact parts.
 
*'''Bounce''' <br />is the single or multiple interruption of conduction between contact parts during the make operation caused by alternating transformation of kinetic to potential energy.
 
*'''Contact wear''' <br />includes all changes on a contact surface. Mechanical and electrical wear must be distinguished.
 
*'''Material transfer''' <br />is the transfer of contact material from one contact part to the other. It occurs mainly during switching of DC loads. The direction of the transfer depends on the load circuit properties and the contact materials used.
 
*'''Arc erosion''' <br />is the loss of material into the surrounding of the contact spot which is generated by electrical arcing. It occurs during contact make as well as break operations.
 
*'''Contact welding''' <br />occurs when melt-liquefied touching areas of the contact parts come in contact with each other. The melting occurs during high current carrying through these areas. During make operations this occurs through bounce arcs, on closed contacts a too high contact resistance or dynamic separation of the contacts due to high short circuit currents can cause the welding of the contacts. The welding then may cause a device failure if the device specific opening forces cannot break the weld connection. <br />
 
*'''Arc movement''' <br />happens when during the break operation a sufficiently high magnetic field is generated which exerts a force on the electrical arc which is then moved from the originating spot towards an arc chute (or arc splitting plates).
 
*'''Arc extinguishing''' <br />means the process of letting the current go to zero and transferring the arcing gap from a conducting to the non-conducting stage. Selecting the most effective extinguishing measures depend mostly on the current characteristics, the current value and the circuit voltage.
 
*'''Recovery''' <br />of an arc gap during contact opening is defined as the process of the electrically conducting plasma of an arc losing its electrical conductivity after reaching current-zero.
 
*'''Symbole used'''
<xr id="fig:Symbole used"/>
<figure id="fig:Symbole used">
[[File:Symbole used.jpg|right|thumb|Symbole used]]
</figure>
==References==