Where on earth did you find that bit of nonsense? More like a second
at twice the rated current.

While I agree Harry's claim was nonsense I think semi-enclosed fuses to
BS3036 are a bit slower than that: AIUI four times the rated current
should blow in less than 1 second; twice the rated current in about 100.
See eg
http://www.aboutelectricity.co.uk/im...rve-bs3036.png or
http://www.tlc-direct.co.uk/Figures/3.13b.gif



--
Robin
reply to address is (meant to be) valid