Clause 6 of IEC 62368-1 requires most wiring & cable to comply with the flammability requirements in IEC 60332-1-2, IEC 60332-1-3, IEC 60332-2-2, or IEC/TS 60695-11-2.
Clause 6 of IEC 62368-1 requires most wiring & cable to comply with the flammability requirements in IEC 60332-1-2, IEC 60332-1-3, IEC 60332-2-2, or IEC/TS 60695-11-2. However, I have difficulty securing wiring from my wire & cable vendors that meet one or more of these standards. Will this be a problem transitioning to IEC 62368-1?
IEC TC108 has implemented a solution in Edition No. 3.
For those familiar with Ed. 2 IEC 62368-1, there are several references in Clause 6 (Electrically-cause Fire) to IEC 60332-1-2, IEC 60332-1-3, IEC 60332-2-2, and IEC/TS 60695-11-2. For example in sub-clause 6.5 (Internal and external wiring), for wiring in PS2 or PS3 circuits the sub-clause states that the insulation on internal or external wiring shall pass the test methods in one of these IEC standards.
However, as you noted, manufacturers have had a challenge sourcing insulated wire that complies with one of these IEC standards. Although UL for several years has offered wire & cable test/certification to these IEC standards, the number of certifications available still have not met the industry need.
(Please see the following document for more info on such test services -
https://industries.ul.com/wp-content/uploads/sites/2/2015/07/WC_IEC60332_a4_ENG.pdf
Industry should find welcome that IEC TC108 will be modifying these flammability requirements in Ed. 3 of IEC 62368-1. Supplementing references to the IEC flammability test standards will be a modifier, 'œ'¦or equivalent,' in addition to an informative note that states 'œWire complying with UL 2556 VW-1 is considered to comply with these requirements.'
The UL 2556 VW-1 test method essentially is equivalent to (harmonized with) the test method in IEC/TS 60695-11-2 so there was TC108 support for formally recognizing readily available VW-1 rated wire as another option. This modification should make it much easier for manufacturers to source wire & cable compatible with 62368-1'™s Clause 6 requirements.
This planned change in IEC 62368-1 is one of numerous examples of IEC TC108 introducing practical, yet sound considerations into the pending Ed. 3 IEC 62368-1. Since these flammability properties are similar regardless of the edition of IEC 62368-1 used, it is reasonable to allow the equivalency provision too for Edition No. 2 of IEC 62368-1 during the transition.