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BS4293 max Zs figures
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<blockquote data-quote="apprentice87" data-source="post: 215849" data-attributes="member: 13534"><p>Hello!</p><p></p><p>This being an RCBO [and you want the "current" part of it to achieve a .2sec disconnect time] you will have to find a characteristic chart that gives the current to operate the device in the required time. How you are going to do this i do not know!!! being as how the thing is obsolete...</p><p></p><p>After that you will soon work it out, because as you already know, it is just a case of dividing 230 by the operating current x 1.25, [conductor temperature and all that] and you have your max measured Zs.</p><p></p><p>Alternatively you can do the more usual 230 divided by the operating current, and then multiply the resultant figure by .8 [it amounts to the same thing 1.25 being the reciprocal of .8] and again you have your max measured Zs.</p><p></p><p>john..</p></blockquote><p></p>
[QUOTE="apprentice87, post: 215849, member: 13534"] Hello! This being an RCBO [and you want the "current" part of it to achieve a .2sec disconnect time] you will have to find a characteristic chart that gives the current to operate the device in the required time. How you are going to do this i do not know!!! being as how the thing is obsolete... After that you will soon work it out, because as you already know, it is just a case of dividing 230 by the operating current x 1.25, [conductor temperature and all that] and you have your max measured Zs. Alternatively you can do the more usual 230 divided by the operating current, and then multiply the resultant figure by .8 [it amounts to the same thing 1.25 being the reciprocal of .8] and again you have your max measured Zs. john.. [/QUOTE]
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BS4293 max Zs figures
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