Difference between revisions of "Contact Physics – Formulas"

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(Created page with "====6.4.2 Contact Physics – Formulas==== *'''Constriction resistance''' Re = D/2a (Single spot contact according to Holm; circular touching spot between clean contact surf...")
 
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====6.4.2 Contact Physics – Formulas====
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|'''Editor''':
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|DODUCO Holding GmbH<br>
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Im Altgefäll 12<br>
  
*'''Constriction resistance'''
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75181 Pforzheim / Germany<br>
  
Re = D/2a
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Phone +49 (0) 7231 602-0<br>
(Single spot contact according to Holm; circular touching spot between clean
 
contact surfaces)
 
Re = D/2Na
 
(Multi-spot contact according to Holm without influence between the N
 
individual spots)
 
Re = D/2 x E ai + 3B D/32N² x E E (sij) i = j
 
(Multi-spot contact according to Greenwood considering the influence between
 
the spots)
 
  
als bild?
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Fax +49 (0) 7231 602-398<br>
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Mail: info@doduco.net<br>
*'''Contact resistance'''
 
RK = Re + Rf
 
 
 
*'''Path resistance'''
 
Rd = Rb + RK
 
 
 
*'''Contact resistance and contact force'''
 
R = 280D ³ E(F · r) K K
 
(According to Holm model for film-free spherical contact surfaces with plastic
 
deformation of the contact material; F < 1 N for typical contact materials) k
 
RK = 9000 D H/ FK
 
(According to Holm model for film-free spherical contact surfaces with plastic
 
deformation of the contact material; F > 5 N for typical contact materials)
 
 
 
 
 
*'''Dynamic contact separation''' (without considering magnetic fields caused by the current path)
 
 
 
FA 0,8 x I²
 
(Rule of thumb with F in N and I in kA)
 
 
 
*'''Contact voltage and max. contact temperature'''
 
T kmax 3200 UK
 
 
 
*'''Contact resistance at higher contact forces (according to Babikow)'''
 
R = cF -m K K
 
For F between 10 and 200 N K
 
c = material dependent proportionality factor
 
m = shape dependent exponent of the contact force
 
 
 
==References==
 
[[Application Tables and Guidance Data for the Use of Electrical Contacts#References|References]]
 

Latest revision as of 11:37, 7 February 2019

Editor: DODUCO Holding GmbH

Im Altgefäll 12

75181 Pforzheim / Germany

Phone +49 (0) 7231 602-0

Fax +49 (0) 7231 602-398


Mail: info@doduco.net