Ron
Fill derating does not apply if it the conduit is installed for protection from physical damage only and is not a complete conduit system.
See Chapter 9, Table 1, Note 2
The subject here is not about derating.
(bold added by me)
2002 NEC Handbook comment after Note 2.
The maximum fill requirements do not apply to short sections of conduit or tubing used for the physical protection of conductors and cables. Cables are commonly protected from physical damage by conduit or tubing sleeves sized to enable the cable to be passed through with relative ease without injuring or abrading the protective jacket of the cable. However, a fitting is required on the end(s) of the conduit or tubing to protect the conductors or cables from abrasion. (See 300.15(C).)
Derating is covered here.
310.15 Ampacities for Conductors Rated 0–2000 Volts.
(B) Tables. Ampacities for conductors rated 0 to 2000 volts shall be as specified in the Allowable Ampacity Table 310.16 through Table 310.19 and Ampacity Table 310.20 through 310.23 as modified by (1) through (6).
(2) Adjustment Factors.
(a) More Than Three Current-Carrying Conductors in a Raceway or Cable. Where the number of current-carrying conductors in a raceway or cable exceeds three, or where single conductors or multiconductor cables are stacked or bundled longer than 600 mm (24 in.) without maintaining spacing and are not installed in raceways, the allowable ampacity of each conductor shall be reduced as shown in Table 310.15(B)(2)(a).
[This message has been edited by WebSparky (edited 08-28-2003).]
