In message <[email protected]>, dated Thu, 25 Feb 2010, Robert Johnson <[email protected]> writes:
>The O and I are intended to indicate the state of the switch (off or >on), not its purpose. But some standards say otherwise - that's the problem. >Multiposition switches can also be labeled with further states like O I >2 3... (that's where the O and I came from). There are many similar >labels for pushbutton, standby and similar operations in IEC 60417. >The function of the switch should also be labeled or otherwise clear. >You are not assured all switches labeled O or I are disconnect >switches, nor is the label O or I reserved for the purpose. They are, according to some standards. >They may even control software functions. In many cases, the disconnect >function is served by the inlet connector and not by a single pole >power switch even though it is labeled O and I. Some standards do not allow a SP switch to be labelled O/I. -- OOO - Own Opinions Only. Try www.jmwa.demon.co.uk and www.isce.org.uk John Woodgate, J M Woodgate and Associates, Rayleigh, Essex UK I should be disillusioned, but it's not worth the effort. - 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 <[email protected]> All emc-pstc postings are archived and searchable on the web at: http://www.ieeecommunities.org/emc-pstc Graphics (in well-used formats), large files, etc. can be posted to that URL. Website: http://www.ieee-pses.org/ Instructions: http://listserv.ieee.org/request/user-guide.html List rules: http://www.ieee-pses.org/listrules.html For help, send mail to the list administrators: Scott Douglas <[email protected]> Mike Cantwell <[email protected]> For policy questions, send mail to: Jim Bacher: <[email protected]> David Heald: <[email protected]>
