A customer noticed that this Littelfuse part 507-1242-ND; 5ST 400-R had suddenly changed a particular marking. The marking in question has the abbreviation “CCC” which stands for Chinese Compulsory Certificate. This is very similar to UL, CE, and CSA. Originally, the marking had a small “s” next to CCC:
New orders no longer had an “s” stamped:
The datasheet still has an small “s” as well on the first page. I did some research and found this article. The article basically says that there used to be small letters (S, EMC, S&E, F, and I) which indicated sub-categories defined in the CCC standards. I did ask our internal team that works in Hong Kong to verify this information and they did find the official Chinese documentation stating this. This is why Littelfuse changed the stamp and why other products may have this change.
