How many #18 MTW conductors used for a discret input signal can I install in a 2" sch 80 pvc conduit?
MTW is not listed in the tables, but going off of the largest diameter #18 in the tables you would be allowed 79 #18's as balsam "guessed".How many #18 MTW conductors used for a discret input signal can I install in a 2" sch 80 pvc conduit?
you're jumping the gun on this one because the largest #18 is .0145 in./sq RHW and your #14 THHN is .0097 in./sq. So the #18 is actually a larger diameter than the #14 meaning less #18's RHW in this same pipe than #14 THHN'sMy homegrown spreadsheet says 118 #14thhns (my minimum size) so it has to be more than that.
My homegrown spreadsheet says 118 #14thhns (my minimum size) so it has to be more than that.
for me this link doesn't help because in Table 310.13(A) it lists MTW conductors and tell you that for sizes 22-12 the thickness of the insulation is.76 mm or 30 mils and your link which lists #18 as .75 mm/sq. I guess I can't help but wonder if one of these is a typo because they sound too similar but one of them is saying .76mm and the other .75 mm/sq. Why would the code list the thickness of the insulation and not the area of the MTW conductors. This bothers me. If the link is correct that #18 is .75 mm/sq and a 2" pvc sched. 80 is 742 mm/sq for 40% fill then you could put 989 of these #18's in this pipe. Sounds like an awfull lot of conductors doesn't it.
after finding the area in mm/sq of #18 MTW to be 5.639 mm/sq assuming I did it right using table 8 conductor properties which is conductors without insulation 1 strand or 7 strand. I used 7 strand as all #18's ...........