Raceway Sizing

jeffwh28

Member
Location
NC
Occupation
Electrician
What trade size ENT raceway is required for four Cat 6 cables having a diameter of 0.22 inches? Explain answer
(a) Trade size 1/2
(b) Trade size 3/4
(c) Trade size 1
(d) Trade size 1-1/4
 

jeffwh28

Member
Location
NC
Occupation
Electrician
Thanks, I thought I understood Chapter 9, but the answer I got is not right, which is 1in because Table 4 under ENT says 3/4 is good for .203 under 40% column. Now I feel like a idiot, question is in inches not sq in.
 

oldsparky52

Senior Member
.22 is the diameter so the sq. in. would be (.11*.11) or .0121* 3.14 = .038

.038*4(cables) = 0.152 for a 40% fill.

1/2" would be too small so 3/4" would be it (if you were bound by the NEC tables).

If I did that wrong, someone will chime in. :)
 

kwired

Electron manager
Location
NE Nebraska
.22 is the diameter so the sq. in. would be (.11*.11) or .0121* 3.14 = .038

.038*4(cables) = 0.152 for a 40% fill.

1/2" would be too small so 3/4" would be it (if you were bound by the NEC tables).

If I did that wrong, someone will chime in. :)
Did not check your math, but you were the first to state that the .22 is cable diameter and that the calculations neccessary need to consider cross sectional area of what will be pulled in vs CSA of the raceway.

True may not be any 40% fill requirement from NEC, but in order to not damage cable, compromise it's performance pulling tension AFAIK can be a big deal, so if you stuff it as full as you can get it there can still be problems. Might be able get away with more fill on a straight run than one with several deflections also.
 

jeffwh28

Member
Location
NC
Occupation
Electrician
Chapter 9 Table 1, 4 cables.
Yes, question doesnt state each cable is .22 inches, so i looked at Table 1 and said 1 inch, but didnt convert to sq inch before looking at chart, so 40% rule apply or not after converting to sq inch?
 

oldsparky52

Senior Member
Yes, question doesnt state each cable is .22 inches, so i looked at Table 1 and said 1 inch, but didnt convert to sq inch before looking at chart, so 40% rule apply or not after converting to sq inch?
I took this to mean that each cable was .22 inches in diameter. Typically you would give the diameter of each cable if it wasn't and you wouldn't add the diameter of each cable together and present that information.

What trade size ENT raceway is required for four Cat 6 cables having a diameter of 0.22 inches?
4 cables = 40% fill
 

kwired

Electron manager
Location
NE Nebraska
Yes, question doesnt state each cable is .22 inches, so i looked at Table 1 and said 1 inch, but didnt convert to sq inch before looking at chart, so 40% rule apply or not after converting to sq inch?
Question you posted says each cable has a diameter of .22 inches.

Knowing about what physical size to expect out of a Cat 6 cable sounds like a reasonable dimension as well.
 

jeffwh28

Member
Location
NC
Occupation
Electrician
I took this to mean that each cable was .22 inches in diameter. Typically you would give the diameter of each cable if it wasn't and you wouldn't add the diameter of each cable together and present that information.



4 cables = 40% fill
Thanks for the help, I was on right path just didnt convert to sq inch before looking at Table 1
 
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