GB/T 15078-2021Testing method for contact resistance of precious metals electrical contact materials (English PDF)

Foreword

This document is in accordance with the provisions of GB/T 1.1-2020 "Guidelines for Standardization Work Part 1: Structure and Drafting Rules of Standardization Documents" Drafting.

This document replaces GB/T 15078-2008 "Measurement method of contact resistance of precious metal electrical contact materials", and GB/T 15078-2008 In comparison, in addition to structural adjustments and editorial changes, the main technical changes are as follows.

a) Added the test at 10°C~40°C (see Chapter 5);

b) The recommended value is changed to 3.3µm/s (see 6.2.5,.2008 edition 5.2.5);

c) The requirements for potential leads have been changed (see 6.4.3,.2008 edition 5.4.3);

d) The requirements for specimens and probes, and specific observation methods for the cleanliness of the specimen surface have been added (see 7.4);

e) Increased non-obvious air flow (see 8.1.1);

f) Added description of 1cN=10-2N (see 8.1.2);

g) Changed the sequence of power on and equipment preheating (see 8.3.3,.2008 edition 7.3.3);

h) Added that K3 is placed in the standard resistance selection position and the interval is 10s, and then the probe is raised (see 8.4.1);

i) Changed the order from low to high (see 8.4.3,.2008 edition 7.4.3);

j) Change the unit of resistance Rn, Rc, Rci to "ohm (ohm)" (see 9.1);

k) Added that as the measurement current and measurement pressure increase, the contact resistance will decrease and the increase in contact time appears to be rapid first Decrease, and then gradually stabilize the decay process, based on this feature, you can select the appropriate contact pressure, test current and test time Conditions to reduce the influence of these main factors on the measurement of contact resistance (see 9.3);

l) The content of the test report is changed (see Chapter 10, Chapter 9 of the.2008 edition).

1 Scope

This document specifies the method for measuring the contact resistance of noble metal electrical contact materials (static).

This document applies to the measurement of the contact resistance of noble metal electrical contact materials. Other metal and alloy electrical contact materials can also be used as reference.

2 Normative references

The contents of the following documents constitute the indispensable clauses of this document through normative references in the text. Among them, dated quotations Only the version corresponding to that date is applicable to this document; for undated reference documents, the latest version (including all amendments) is applicable to this document.

GB/T 8170 Numerical rounding rules and the expression and determination of limit values

3 Terms and definitions

The following terms and definitions apply to this document.