MT 60079-35 - TC 31/MT 60079-35

IEC 60079-35-2:2011 details those performance and other safety features of caplights, including those with a point of connection for another equipment, not covered in IEC 60079-35-1, but which are important for the safety and working conditions of the user. It may also be applied to caplights for use in mines not likely to be endangered by firedamp. This first edition of IEC 60079-35-2 cancels and replaces the second edition (2005) of IEC 62013-2 published in 2005 and constitutes a full technical revision. The general revision and updating of Edition 2 of IEC 62013-2 has been necessitated by the advent of new technologies related to caplight design, in particular those related light-emitting diode (LED) light sources. It is intended that there should be a stronger link between Part 1 (Construction) and Part 2 (Performance) of this Standard by upgrading the reference in the Scope of part 1 from a note to a requirement. In addition as this Standard is now to become one of the IEC 60079 series, changes have been made to bring it more in line with others in the series by cross referencing. This has enabled there to be a reduction in the number and length of clauses in the Standard.

IEC 60079-35-1:2011 specifies requirements for the construction, testing and marking of caplights, including caplights with a point of connection for other equipment, for use in mines susceptible to firedamp (Group I - electrical equipment for explosive gas atmospheres as defined in IEC 60079-0). It deals only with the risk of the caplight becoming a source of ignition. The requirements for performance are in IEC 60079-35-2. This standard supplements and modifies the general requirements of IEC 60079-0 except as indicated in Table 1. This first edition cancels and replaces the second edition of IEC 62013-1, published in 2005, and constitutes a full technical revision. The main technical differences with respect to the previious edition are:
- the introduction of a means to achieve an equipment protection level (EPL) of Ma;
- the introduction of a single clause relating to equipment construction replacing individual specific clauses for the headpiece, battery, cable and external charging contacts;
- the deletion of statements relating to surface temperature, the rewording of statements relating to creepage and clearance and the addition of statements relating to thermal protection, electronic assemblies and additional circuitry;
- specific referenc to lithium cells;
- the addition of statements relating to battery recharging and protection against deep discharge.