Definition - What does Eurocard mean?
The Eurocard is a European standard for printed circuit boards (PCB) designed to be plugged into and mounted on a standardized subrack. It is standardized in size with dimensions of 100 mm × 160 mm and a thickness of 1.6 mm, and originally defined in IEC-60297-3 so that industry machines and panels could become standardized and more economical. It is used in many industries such as manufacturing, telecommunication and military.
Techopedia explains Eurocard
The Eurocard is a standard size for manufactured printed circuit boards made to fit into designated subracks. Though the size of the PCB is standardized, the connector that it uses is not, though there are ones that are commonly used such as DIN 41612, which is commonly used with the Eurocard standard.
The standard Eurocard card size is 100 mm × 160 mm, but there are other sizes such as the double Eurocard (233.35 mm × 160 mm) and the half Eurocard (100 mm × 80 mm), which to an extent are sized as they are named. The rack enclosures are sized in multiples of 3U, with 1 unit being 44.45 mm and with the cards being 33.35 mm shorter than the rack. So a 3U rack would have a height of 133.35 mm and it would accommodate a regular Eurocard with 100 mm height, which is 33.35 shorter than the 3U rack.