For IEC 62368-1:2018 (3rd Ed.), Cl. 8.6.5, why was the horizontal force test value increased to 20% of the equipment weight, or max 250N, from IEC 62368-1:2014'™s (2nd Ed) values of 13% and 100N, respectively?
This horizontal force test applies to constructions with controls or a display and is intended to simulate the force of a child who might climb onto the equipment and engage front-mounted user controls or the moving images on the display. The original horizontal test force applied was 13% of the equipment mass or 100 N, whichever was less, applied to both MS2 and MS3 constructions and was developed to address many field incidents of CRT TVs / monitors in the late 20th century; the details of which are noted in 8.6.5 of '˜the rationale document,'™ IEC TR 62368-2. However, more recently, flat panel display TVs / monitors have higher inherent instability in their design, especially if a child were to lean on the edges or controls, and such flat panel display products also are increasing in size/weight. Therefore, IEC TC108 revisited the 8.6.5 requirements, and in IEC 62368-1:2018, the force was increased to either 20% of equipment mass or 250 N, whichever is less, to anticipate better today'™s larger flat display units considered MS3 (but MS3 only). Please note, for applicable products considered MS2, in IEC 62368-1:2018, the Horizontal Force Stability (8.6.5) requirement has been replaced by Static Stability (8.6.2.2). Also, for applicable products considered MS3, the external horizontal force test remains only one option in 8.6.5, with two variations of the 15-degree tilt test available as alternate performance options.