BS 5992-4:1983

National foreword
Committees responsible
Section one - General and definitions
1 General
1.1 Scope and object
1.2 General requirements
2 Terms and definitions
2.1 Application category of contacts
3 Standard values
3.1 Application categories of contacts
Section two - Standard values for categories 0 and 1
4 Contact loads
4.1 D.C. and a.c. (50 Hz or 60 Hz) resistive loads
4.2 D.C. inductive loads
4.3 Capacitive load
4.4 D.C. relay load
4.5 D.C. open-ended cable loads (floating cable)
4.6 D.C. cable loads combined with resistive load
4.7 D.C. cable load combined with relay load
Section three - Standard values for categories 2 and 3
5 Contact loads
5.1 D.C. and a.c. (50 Hz, 60 Hz or 400 Hz) resistive
     loads
5.2 Inductive loads
5.3 Capacitive loads
5.4 Relay load

Specifies characteristics of standard types of contact load to be used in endurance tests of electrical relay contacts over ranges of voltages and currents corresponding to defined application categories. Also lists preferred values for contact loads.

This standard applies to contact assemblies of all types of relays covered by the Publication 255 series: Electrical Relays.

This standard specifies preferred characteristics of the contact loads to be used in endurance tests of electrical relay contacts over the ranges of voltages and currents defined by application categories. Preferred values are given for various types of load including relay and cables.

As a result of further consideration the title and values of various tables differ slightly from those published in IEC Publication 225-0-20: Contact Performance of Electrical Relays.

The detail specifications²⁾ shall refer to these preferred values of contact loads but for a particular application, additional characteristics may be defined (e.g. inrush current in a contact load circuit, lamp load or motor load).