earlejohnson
Member
- Location
- ga.
Heard a new one today looked and can't find it someone told me today that by code you are not allowed to put any more than ten wires in any size conduit. As always thanks for your help.
It's a common-place-ole-wives-tale based on the fact that your 10th current carrying conductor requires a 50% derating which can be the killer on a circuit utilizing #12 or #14. Often times rather than providing an explanation of de-rating, electricians are told "no more than 10 wires".
Table 310.15(B)(3)(a) Adjustment Factors for More ThanThree Current-Carrying Conductors in a Raceway or CableNumber ofConductorsPercent of Values inTable 310.15(B)(16) throughTable 310.15(B)(19) asAdjusted for AmbientTemperature if Necessary
4–6 807–9 7010–20 5021–30 4531–40 4041 and above 35Number of conductors is the total number of conductors in the racewayor cable adjusted in accordance with 310.15(B)(5) and (6).
I wanted to point out that if no more than ten conductors was the rule why would this table go beyond 10 conductors?.
Heard a new one today looked and can't find it someone told me today that by code you are not allowed to put any more than ten wires in any size conduit. As always thanks for your help.
You know whatever they is going to be wrong when they say "Wires" and not conductors.
I know a school that has 108 #8's in a 3 inch run of RMC. State inspector approved it. I was a second year apprentice when we did the pull. Ripped tandem tuggers off guard rail, breaking the logging chain holding it there. The meter on the lead tugger read 2900 lbs. just before the break.