612021 Web SeriesIJPNC72 JPNC Additional Explanations for 616223DC

61(2021 Web. Series-I/JPNC)72 JPNC Additional Explanations for 61/6223/DC (61/6256/INF) document IEC 60335 -2 -14

The concerned proposal 3 rd paragraph of clause 20. 2 The test probe is not applied to feed openings having a throat with the following dimensions: – a height of at least 100 mm, measured from the upper edge of the cutting blade; – an average of the maximum and minimum cross-sectional dimensions of the feed opening that does not exceed 65, 5 mm; – a maximum cross-sectional dimension of the feed opening that does not exceed 76 mm. For other feed openings, a test probe similar to test probe B of IEC 61032 but having a circular stop face with a diameter of 50 mm, instead of the non-circular face is applied. The sentence added by the proposal

Our comment (JP 06) Comment: We do not support the proposal for the following reasons. The test probe having a stopper with a diameter of 50 mm as specified in the proposal will allow larger feed openings and make it unsafe. If the throat only has a minimum height of 80 mm above the cutting blade and minimum cross-sectional dimension of 50 mm, the stopper is blocked by the throat and makes it compliant (unsafe), as shown by the below figure. Test probe B Test probe similar to test probe B of IEC 61032 but having a circular stop face with a diameter of 50 mm Proposed change: Delete the proposal at line 51 -52.

Our additional explanation We made a dummy wider openings of a throat to show a demonstration. 49 mm 100 mm By adding the white parts to test probe B, we made a test probe equivalent to “test probe similar to test probe B but having a circular stop face with a diameter of 50 mm” equivalent to

The proposal The existing Part 2 -14 Test probe B Thicker test probe similar to test probe B but having a circular stop face with a diameter of 50 mm The thicker stopper cannot pass through the opening by the additional white parts Cutting blade The finger goes down deeper, and reach cutting blades. Not compliant The finger does not go down deep, and not reach cutting blades. Compliant Allow the unsafe construction having the wider opening and shorter distance to the cutting blade.

Allow the unsafe construction having the wider opening and shorter distance to the cutting blade. Cutting blade Part 2 -14 has appliances with more dangerous moving part (ex. cutting blades) than other Part 2 s do. - According to the proposal, with the thicker test probe based on Part 1, it allows unsafe condition that an adult hand passes through the wider opening, and a finger easily touches the cutting blades placed at a shorter distance. - According to the existing Part 2 -14, with test probe B, it does not allow the above construction.