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Student & Learning Zone - City & Guilds
help with questions on 2391
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<blockquote data-quote="TonyMitchell" data-source="post: 490639" data-attributes="member: 32191"><p>As the OP seems to have disappeared from this thread, I'll give it a go, as am new to RFCs &amp; still learning (I do temporary power, where it's all radials)...</p><p></p><p>OSG Table I1 shows (R1+R2) for 4mm2+1.5mm2 CPC as 16.71mΩ/metre</p><p></p><p>(58*16.71)/1000 = 0.97Ω</p><p></p><p>97/4 = 0.24Ω</p><p></p><p>I'd say the multiple choice answer is (b) 0.27Ω - approximately 1/4 of the (R1+R2) plus cpc loop resistances.</p><p></p><p>This is well within the maximum of 1.1Ω shown in GN3 Table A4, for a 32A Type B protective device.</p></blockquote><p></p>
[QUOTE="TonyMitchell, post: 490639, member: 32191"] As the OP seems to have disappeared from this thread, I'll give it a go, as am new to RFCs & still learning (I do temporary power, where it's all radials)... OSG Table I1 shows (R1+R2) for 4mm2+1.5mm2 CPC as 16.71mΩ/metre (58*16.71)/1000 = 0.97Ω 97/4 = 0.24Ω I'd say the multiple choice answer is (b) 0.27Ω - approximately 1/4 of the (R1+R2) plus cpc loop resistances. This is well within the maximum of 1.1Ω shown in GN3 Table A4, for a 32A Type B protective device. [/QUOTE]
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help with questions on 2391
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