Difference between revisions of "Switching Contacts"

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<li>'''Effects during switching operations'''</li>
 
<li>'''Effects during switching operations'''</li>
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<xr id="fig:Contact_opening_with_arc_formation_schematic"/><!--Fig. 6.7:--> Contact opening with arc formation schematic
 
  
 
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<li>'''Influence of out-gasing from plastics'''</li>
 
<li>'''Influence of out-gasing from plastics'''</li>
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<xr id="fig:Histogram_of_the_contact_resistance_Rk"/><!--Fig. 6.9:--> Histogram of the contact resistance Rk of an electroplated palladium layer (3 μm) with and without hard gold flash plating (0.2 μm) after exposure with different plastic materials
 
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<xr id="fig:Contact resistance with exposure to out gasing from plastics"/><!--Fig. 6.10:--> Contact resistance with exposure to out gasing from plastics as a function of numbers of operations at 6 V<sub>DC</sub>,100 mA: 1 Silicon containing plastic; 2 Plastics with strongly out-gasing components; 3 Plastics with minimal out-gasing components
 
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<li>'''Influence of corrosive gases on the contact resistance'''</li>
 
<li>'''Influence of corrosive gases on the contact resistance'''</li>
  
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<xr id="fig:Distribution of cumulative frequency H of the contact resistance for solid contact rivets"/><!--Fig. 6.11:--> Distribution of cumulative frequency H of the contact resistance for solid contact rivets after 10 days exposure in a three-component test environment with 400 ppb each of H<sub>2</sub>S, SO<sub>2</sub> and NO<sub>2</sub> at 25°C, 75% RH; Contact force 10cN; Measuring parameters: ≤ 40 mV<sub>DC</sub>,10 mA; Probing
 
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contact: Gold rivet
 
  
 
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<li>'''Material transfer'''</li>
 
<li>'''Material transfer'''</li>
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<xr id="fig:Material transfer under DC load"/><!--Fig. 6.12:--> Material transfer under DC load a) Cathode; b) Anode. <br /> Material: AgNi0.15; Switching parameters: 12V<sub>DC</sub>, 3 A, 2x10<sup>6</sup> operations
 
  
 
<div class="multiple-images"><figure id="fig:Material transfer under DC load">[[File:Material transfer under DC load.jpg|left|thumb|<caption>Material transfer under DC load a) Cathode; b) Anode. <br /> Material: AgNi0.15; Switching parameters: 12V<sub>DC</sub>, 3 A, 2x10<sup>6</sup> perations</caption>]]</figure></div>
 
<div class="multiple-images"><figure id="fig:Material transfer under DC load">[[File:Material transfer under DC load.jpg|left|thumb|<caption>Material transfer under DC load a) Cathode; b) Anode. <br /> Material: AgNi0.15; Switching parameters: 12V<sub>DC</sub>, 3 A, 2x10<sup>6</sup> perations</caption>]]</figure></div>
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<li>'''Arc erosion'''</li>
 
<li>'''Arc erosion'''</li>
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<xr id="fig:Arc erosion of a AgSnO2 contact pair after extreme arcing conditions"/><!--Fig. 6.13:--> Arc erosion of a Ag/SnO<sub>2</sub> contact pair after extreme arcing conditions a) Overall view; b) Partial detail view
 
  
 
<div class="multiple-images"><figure id="fig:Arc erosion of a AgSnO2 contact pair after extreme arcing conditions">[[File:Arc erosion of a AgSnO2 contact pair after extreme arcing conditions.jpg|left|thumb|<caption>Arc erosion of a Ag/SnO<sub>2</sub> contact pair after extreme arcing conditions a) Overall view; b) Partial detail view</caption>]]</figure></div>
 
<div class="multiple-images"><figure id="fig:Arc erosion of a AgSnO2 contact pair after extreme arcing conditions">[[File:Arc erosion of a AgSnO2 contact pair after extreme arcing conditions.jpg|left|thumb|<caption>Arc erosion of a Ag/SnO<sub>2</sub> contact pair after extreme arcing conditions a) Overall view; b) Partial detail view</caption>]]</figure></div>
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<li>'''Contact welding'''</li>
 
<li>'''Contact welding'''</li>
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<xr id="fig:Micro structure of a welded contact pair after extremely high current load"/><!--Fig. 6.14:--> Micro structure of a welded contact pair (Ag/SnO<sub>2</sub>88/12 - Ag/CdO88/12) after extremely high current load. a) Ag/SnO<sub>2</sub>88/12; b) Ag/CdO88/12
 
  
 
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Revision as of 14:37, 2 December 2022

Switching Contacts

  • Effects during switching operations
    • Figure 1: Contact opening with arc formation (schematic)
  • Influence of out-gasing from plastics
    • Figure 2: Histogram of the contact resistance RK of an electroplated palladium layer (3 μm) with and without hard gold flash plating (0.2 μm) after exposure with different plastic materials
    Figure 3: Contact resistance with exposure to out-gasing from plastics as a function of numbers of operations at 6 VDC,100 mA: 1 Silicon containing plastic; 2 Plastics with strongly out-gasing components; 3 Plastics with minimal out-gasing components


  • Influence of corrosive gases on the contact resistance


    • Figure 4: Distribution of cumulative frequency H of the contact resistance for solid contact rivets after 10 days exposure in a three-component test environment with 400 ppb each of H2S, SO2 and NO2 at 25°C, 75% RH; Contact force 10cN; Measuring parameters: ≤ 40 mVDC,10 mA; Probing contact: Gold rivet


    Influences on contact areas in relays
  • Contact Phenomena under the influence of arcing Matertia
    • Material transfer
      • Figure 5: Material transfer under DC load a) Cathode; b) Anode.
      Material: AgNi0.15; Switching parameters: 12VDC, 3 A, 2x106 perations
    • Arc erosion
      • Figure 6: Arc erosion of a Ag/SnO2 contact pair after extreme arcing conditions a) Overall view; b) Partial detail view
    • Contact welding
      • Figure 7: Micro structure of a welded contact pair (Ag/SnO288/12 - Ag/CdO88/12) after extremely high current load. a) Ag/SnO288/12; b) Ag/CdO88/12

References

References

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