1 Scope

1.1 This standard states basic construction, test, and marking requirements for fixture wires. Fixture wires are single conductor and are of the following types:

  600 volt Types:

PTF, PTFF, PAF, PAFF, KF-2, KFF-2, PF, PFF, PGF, PGFF, SF-2, SFF-2, ZF, ZFF, ZHF, TF, TFF, TFN, TFFN, RFH-2, FFH-2, FFHH-2, HF, HFF, RFHH-2, and RFHH-3

  300 volt Types:

KF-1, KFF-1, SF-1, SFF-1, RFH-1, XF, and XFF

These types are for use as specified in Article 402 and other applicable parts of the National Electrical Code (NEC), ANSI/NFPA 70. These types are as described individually in index – of this standard.

Summary of Topics:

This new edition of ANSI/UL 66 dated January 18, 2023 includes the following:

– Addition of Types RFH-1, HF and HFF throughout the Standard; 1.1, 4.1, Table 4.8, Table 4.10, 6.1.2, Table 6.1, Table 6.2, 10.1 (title), 10.1.1, 10.3 (title), 10.3.1.1, Table 10.2, Table 10.3, Table 10.4, Table 10.5, Table 10.6, Table 13.1, Table 16.1, 18.1, Section 21 (title), and Table 26.1;

– Updated References from UL 1581 to UL 2556; Table 4.3, Table 4.5, Table 4.6, Table 4.7, Table 4.8, 6.4.3, 17.1 – 17.3, 18.1 and 18.2