Difference between revisions of "General Rules for Dimensioning of Contacts"

From Electrical Contacts
Jump to: navigation, search
(Created page with "====6.4.6 General Rules for Dimensioning of Contacts==== *'''Recommended Minimum Contact Forces at Slightly Sliding Contact Make:''' Gold 0.03 N Silver 0.1 N Tungsten 0.5 N ...")
 
 
(31 intermediate revisions by 4 users not shown)
Line 1: Line 1:
−
====6.4.6 General Rules for Dimensioning of Contacts====
+
===<!--6.4.6-->General Rules for Dimensioning of Contacts===
  
−
*'''Recommended Minimum Contact Forces at Slightly Sliding
+
'''Recommended Minimum Contact Forces at Slightly Sliding Contact Make:'''
−
Contact Make:'''
 
  
−
Gold 0.03 N
+
<table class="twocolortable" style="text-align: left; font-size: 12px;width:40%">
−
Silver 0.1 N
+
<tr>
−
Tungsten 0.5 N
+
<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:'''
+
'''Contact Force Recommendations:'''
  
−
Signal relays >3 cN
+
{| class="twocolortable" style="text-align: left; font-size: 12px;width:40%"
−
AC power relays > 20 cN
+
|-
−
Automotive relays > 20 cN
+
|Signal relays    
−
Motor switches (Contactors) 0.05 - 0.08 N/A
+
|&ge; 3 cN
−
(Silver – Metal oxide contacts)
+
|-
−
Power switches 0.1 - 0.2 N/A
+
|AC power relays  
−
Connectors > 30 cN/contact element
+
|&ge; 20 cN
−
(Gold coating)
+
|-
−
Connectors > 50 cN/contact element
+
|Automotive relays
−
(Silver coating)
+
|&ge; 20 cN
−
Connectors > 1 N/contact element
+
|-
−
(Tin coating)
+
|Motor switches (Contactors)<br />(Silver – Metal oxide contacts)
 +
|0.05 - 0.08 N/A
 +
|-
 +
|Power switches
 +
|0.1 - 0.2 N/A
 +
|-
 +
|Connectors<br />(Gold coating)
 +
|&ge; 30 cN/contact element
 +
|-
 +
|Connectors<br />(Silver coating)
 +
|&ge; 50 cN/contact element
 +
|-
 +
|Connectors<br />(Tin coating)
 +
|&ge; 1 N/contact element
 +
|}
  
−
*'''General Rules for Dimensioning of Contact Rivets'''
 
−
bild
 
  
−
*'''Head diameter for electrical loads'''
+
'''General Rules for Dimensioning of Contact Rivets'''
  
−
For AC currents: approx. 1 – 1.5 A/mm²
+
[[File:General Rules for Dimensioning of Contact Rivets.jpg|left|thumb|Figure 1: General Rules for Dimensioning of Contact Rivets]]
−
For 1 A min. 2 mm head diameter
+
{| class="twocolortable" style="text-align: left; font-size: 12px;width:100%"
−
10 A approx. 3 – 3.5 mm head diameter
+
|-
−
20 A approx. 5 mm head diameter
+
!Dimensioning
−
For DC currents: approx. 0.5 – 0.8 A/mm²
+
!Solid Rivets (1)
 +
!Composite Rivets (2)
 +
|-
 +
|a : d     
 +
|1.5 : 1 bis 2.5 : 1
 +
|2 : 1 bis 2.5 : 1
 +
|-
 +
|a : b     
 +
|2.5 : 1 bis 10 : 1
 +
|3 : 1 bis 5 : 1
 +
|-
 +
|c : b     
 +
|&ge; 1 : 1
 +
|&ge; 1 : 1
 +
|-
 +
|b : s     
 +
|
 +
|&ge; 2 : 1
 +
|-
 +
|s<sub>min</sub>   
 +
|
 +
|&#8776; 0.3 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. 6.19: Failure probability of a contact as a
+
'''Failure Probability of Single and Double (Bifurcated) Contacts''' (according to Thielecke)
−
function of the current (according to
+
 
−
Kirchdorfer); Ag/Ni10; F = 0.45 N; U = 24 V
+
{| 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.jpg|left|thumb|Figure 2: Failure probability of a contact as a function 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 to Kirchdorfer); 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]]

Latest revision as of 14:01, 26 January 2023

General Rules for Dimensioning of Contacts

Recommended Minimum Contact Forces at Slightly Sliding Contact Make:

Gold 0.03 N
Silver 0.1 N
Tungsten 0.5 N

Contact Force Recommendations:

Signal relays ≥ 3 cN
AC power relays ≥ 20 cN
Automotive relays ≥ 20 cN
Motor switches (Contactors)
(Silver – Metal oxide contacts) 		0.05 - 0.08 N/A
Power switches 0.1 - 0.2 N/A
Connectors
(Gold coating) 		≥ 30 cN/contact element
Connectors
(Silver coating) 		≥ 50 cN/contact element
Connectors
(Tin coating) 		≥ 1 N/contact element


General Rules for Dimensioning of Contact Rivets

Figure 1: General Rules for Dimensioning of Contact Rivets
Dimensioning Solid Rivets (1) Composite Rivets (2)
a : d 1.5 : 1 bis 2.5 : 1 2 : 1 bis 2.5 : 1
a : b 2.5 : 1 bis 10 : 1 3 : 1 bis 5 : 1
c : b ≥ 1 : 1 ≥ 1 : 1
b : s ≥ 2 : 1
smin ≈ 0.3 mm



Failure Probability of Single and Double (Bifurcated) Contacts (according to Thielecke)

Contact force[N] Single contact
Ag AuNi 5, Pt Ag AuNi 5, Pt
0.04 1 x 10-4 2 x 10-8
0.1 2 x 10-3 4 x 10-5 8 x 10-5 8 x 10-9
0.2 1 x 10-4 8 x 10-6 4 x 10-6 4 x 10-8
0.3 5.5 x 10-6 1.5 x 10-6 1.8 x 10-7 3.2 x 10-10


Figure 2: Failure probability of a contact as a function of the voltage (according to Kirchdorfer); Ag/Ni10; 10 mA
Figure 3: Failure probability of a contact as a function of the current (according to Kirchdorfer); Ag/Ni10; Fk = 0.45 N; U = 24 V

References

References

Retrieved from "https://www.electrical-contacts-wiki.com/index.php?title=General_Rules_for_Dimensioning_of_Contacts&oldid=5520"