====6.4.2 Contact Physics – Formulas===={| |'''Editor''':|DODUCO Holding GmbH<br> Im Altgefäll 12<br>
*'''Constriction resistance'''75181 Pforzheim / Germany<br>
Re = D/2a(Single spot contact according to Holm; circular touching spot between cleancontact surfaces)Re = D/2Na(Multi-spot contact according to Holm without influence between the Nindividual spots)Re = D/2 x E ai Phone + 3B D/32N² x E E 49 (sij0) i = j(Multi7231 602-spot contact according to Greenwood considering the influence betweenthe spots)0<br>
als bild?Fax +49 (0) 7231 602-398<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 plasticdeformation of the contact material; F Mail: info@doduco.net< 1 N for typical contact materials) kRK = 9000 D H/ FK(According to Holm model for film-free spherical contact surfaces with plasticdeformation of the contact material; F br> 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 KFor F between 10 and 200 N Kc = material dependent proportionality factorm = shape dependent exponent of the contact force ==References==[[Application Tables and Guidance Data for the Use of Electrical Contacts#References|References]]
