====<!--6.4.6 -->General Rules for Dimensioning of Contacts====
*'''Recommended Minimum Contact Forces at Slightly SlidingContact Make:'''
<table class="twocolortable" style="text-align: left; font-size: 12px;width:40%"><tr><td>Gold </td> <td>0.03 N</td></tr><tr><td>Silver </td><td>0.1 N</td></tr><tr><td>Tungsten </td><td>0.5 N</td></tr></table>
*'''Contact Force Recommendations:'''
{| class="twocolortable" style="text-align: left; font-size: 12px;width:40%"|-|Signal relays > |≥ 3 cN|-|AC power relays > |≥ 20 cN|-|Automotive relays > |≥ 20 cN|-|Motor switches (Contactors) <br />(Silver – Metal oxide contacts)|0.05 - 0.08 N/A(Silver – Metal oxide contacts)|-|Power switches |0.1 - 0.2 N/A|-|Connectors <br /> (Gold coating)|≥ 30 cN/contact element|-|Connectors<br />(Gold Silver coating)Connectors > |≥ 50 cN/contact element|-|Connectors<br />(Silver Tin coating)Connectors > |≥ 1 N/contact element(Tin coating)|}
*'''General Rules for Dimensioning of Contact Rivets'''
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*'''Head diameter General Rules for electrical loadsDimensioning of Contact Rivets'''
For AC currents[[File: approxGeneral Rules for Dimensioning of Contact Rivets. jpg|left|thumb|Figure 1 – : General Rules for Dimensioning of Contact Rivets]]{| class="twocolortable" style="text-align: left; font-size: 12px;width:100%"|-!Dimensioning!Solid Rivets (1)!Composite Rivets (2)|-|a : d |1.5 : 1 bis 2.5 A/mm²: 1For |2 : 1 A min. bis 2 mm head diameter10 A approx. 3 – 3.5 mm head diameter: 1 |-|a : b 20 A approx|2. 5 mm head diameter: 1 bis 10 : 1For DC currents|3 : approx. 0.1 bis 5 – : 1|-|c : b |≥ 1 : 1|≥ 1 : 1|-|b : s ||≥ 2 : 1|-|s<sub>min</sub> ||≈ 0.8 A/mm²3 mm|}
*'''Head radius R for electrical loads'''
for I < 1 A R 1,5 mm
I = 6 A R 5 mm
I = 10 A R 10 mm
I = 20 A R 15 mm
*'''Failure Probability of Single and Double (Bifurcated) Contacts''' (according to Thielecke)
Fig. 6.18: Failure probability of a contact as a
function of the voltage (according to Kirchdorfer);
Ag/Ni10; 10 mA
Fig'''Failure Probability of Single and Double (Bifurcated) Contacts''' (according to Thielecke) {| class="twocolortable" style="text-align: left; font-size: 12px;width:100%"|-!Contact force[N] !colspan="4" style="text-align:center"|'''Single contact'''|-! !Ag!AuNi 5, Pt!Ag!AuNi 5, Pt|-|0. 04 ||1 x 10<sup>-4</sup>||2 x 10<sup>-8</sup>|-|0.1 |2 x 10<sup>-3</sup>|4 x 10<sup>-5</sup>|8 x 10<sup>-5</sup>|8 x 10<sup>-9</sup>|-|0.2|1 x 10<sup>-4</sup>|8 x 10<sup>-6</sup>|4 x 10<sup>-6</sup>|4 x 10<sup>-8</sup>|-|0.3|5.5 x 10<sup>-6</sup>|1.5 x 10<sup>-6</sup>|1.8 x 10<sup>-7</sup>|3.2 x 10<sup>-10</sup>|} <div class="multiple-images"><figure id="fig:Failure probability of a contact as a function of the voitage">[[File:Failure probability of a contact as a function of the voitage.19jpg|left|thumb|Figure 2: Failure probability of a contact as afunction of the voltage (according to Kirchdorfer); Ag/Ni10; 10 mA]]</figure> <figure id="fig:Failure probability of a contact as a function of the current">[[File:Failure probability of a contact as a function of the current.jpg|left|thumb|Figure 3: Failure probability of a contact as a function of the current (according toKirchdorfer); Ag/Ni10; F <sub>k</sub> = 0.45 N; U = 24 V]]</figure></div><div class="clear"></div> ==References==[[Application Tables and Guideline Data for Use of Electrical Contact Design#References|References]] [[de:Faustregeln_für_die_Kontaktdimensionierung]]
