Thanks Brian, I knew about the prefixes Fs & Ts but not the M. I tried looking for source information in the past and at the time I was certifying to a VDE standard through LGA Nuremberg. I was also told the acronyms used different German terms, but fortunately the first letters were the same as for English words.
A quick check again today and I found: [image: image.png] Thanks -Doug Laporte, Colorado USA doug...@gmail.com <https://www.linkedin.com/in/coloradocomplianceguy/> (UTC -07:00) Mountain Time (US-MST) On Wed, Mar 2, 2022 at 2:07 PM Brian Kunde <bkundew...@gmail.com> wrote: > I do not know where the information I have originally came from, but I got > this and have been using this for over 30 years: > > FF = Very Fast Acting > F = Fast Acting (Common) > M = Medium Time Lag > T = Time Lag (Common) > TT = Long Time Lag > > I got this from Bud Lang who was our Safety Guru at Heath Kit many years > ago. > > The Other Brian > > On Tue, Mar 1, 2022 at 5:33 PM Douglas E Powell <doug...@gmail.com> wrote: > >> All, >> >> Over the years, I've seen various ways people include a caution or >> warning, in their user documents or product labels, for replacement fuses. >> Similar to: "replace only with same type and rating of fuse"; followed by >> a code: T1.6AH250V. And for those who may not understand the code, they may >> sometimes add in parentheses some variant of "(1.6 Amp time-lag, ~250V, >> high breaking capacity)". >> >> So now to my question, US manufacturers sometimes use the phrase >> "SLO-BLO" or "Slow Blow" instead of Time-Lag or Time-Delay. Are these terms >> commonly used internationally and if so, are they clearly understood? >> >> I took some time to look up SLO-BLO and found it's a registered trademark >> for Littelfuse going back to 1957, and it has been continuously renewed >> since that time. >> >> Incidentally, a German Engineer once told me the way he would designate a >> fuse type for a variety of tripping characteristics was in this order from >> very slow to very fast: TT1.0A250V, T1.0A250V, 1.0A250V, F1.0A250V, >> FF1.0A250V. >> >> Thanks, -Doug >> >> >> Douglas E Powell >> Laporte, Colorado USA >> >> (UTC -07:00) Mountain Time (US-MST) >> >> >> >> >> - >> ---------------------------------------------------------------- >> >> This message is from the IEEE Product Safety Engineering Society emc-pstc >> discussion list. To post a message to the list, send your e-mail to < >> emc-p...@ieee.org> >> >> All emc-pstc postings are archived and searchable on the web at: >> http://www.ieee-pses.org/emc-pstc.html >> >> Attachments are not permitted but the IEEE PSES Online Communities site >> at http://product-compliance.oc.ieee.org/ can be used for graphics (in >> well-used formats), large files, etc. >> >> Website: http://www.ieee-pses.org/ >> Instructions: http://www.ieee-pses.org/list.html (including how to >> unsubscribe) <http://www.ieee-pses.org/list.html> >> List rules: http://www.ieee-pses.org/listrules.html >> >> For help, send mail to the list administrators: >> Scott Douglas <sdoug...@ieee.org> >> Mike Cantwell <mcantw...@ieee.org> >> >> For policy questions, send mail to: >> Jim Bacher <j.bac...@ieee.org> >> David Heald <dhe...@gmail.com> >> > - ---------------------------------------------------------------- This message is from the IEEE Product Safety Engineering Society emc-pstc discussion list. To post a message to the list, send your e-mail to <emc-p...@ieee.org> All emc-pstc postings are archived and searchable on the web at: http://www.ieee-pses.org/emc-pstc.html Attachments are not permitted but the IEEE PSES Online Communities site at http://product-compliance.oc.ieee.org/ can be used for graphics (in well-used formats), large files, etc. Website: http://www.ieee-pses.org/ Instructions: http://www.ieee-pses.org/list.html (including how to unsubscribe) List rules: http://www.ieee-pses.org/listrules.html For help, send mail to the list administrators: Scott Douglas <sdoug...@ieee.org> Mike Cantwell <mcantw...@ieee.org> For policy questions, send mail to: Jim Bacher: <j.bac...@ieee.org> David Heald: <dhe...@gmail.com>
