JeremyO
Member
- Location
- Bristol, Tennessee
- Occupation
- Director
I need help regarding the use of single conductor wiring methods with cable tray or basket. Anixter has produced a helpful article regarding single-conductor cables permitted in cable tray applications:
"Article 392 of the NEC provides the basic requirements for installations using cable tray. The respective article for the cable type must also be followed. Table 392.10 (see Table 1) lists the type of cable that is allowed to be installed in tray and the types of raceway that can be used. This table includes almost all common types of wire and cable found in the NEC.
Cable types that are not presented in the table include single-conductor building wire types such as THHN/THWN, XHHW and RHH/RHW. Article 392 does allow these types to be installed as power conductors if they are larger than 1/0 and marked for use in tray. Ground wires must be larger than 4 AWG but are not required to be marked."
My question is are there any additional wiring methods that would permit single conductors smaller than 1/0 (typically 10awg and below) to be used in cable tray? For a worst-case example, what if multiple SIS (or any other insulation class) individual conductors were placed in a secondary product (ex. Panduit) that is mounted in the tray. Is there a product on the market or a stipulation in the code that would permit single conductor installations? In many cases, the need for individual conductor wiring (not multi-conductor tray-cable) is necessary and multiple conduit runs are not cost/space effective. Any suggestions?
"Article 392 of the NEC provides the basic requirements for installations using cable tray. The respective article for the cable type must also be followed. Table 392.10 (see Table 1) lists the type of cable that is allowed to be installed in tray and the types of raceway that can be used. This table includes almost all common types of wire and cable found in the NEC.
Cable types that are not presented in the table include single-conductor building wire types such as THHN/THWN, XHHW and RHH/RHW. Article 392 does allow these types to be installed as power conductors if they are larger than 1/0 and marked for use in tray. Ground wires must be larger than 4 AWG but are not required to be marked."
My question is are there any additional wiring methods that would permit single conductors smaller than 1/0 (typically 10awg and below) to be used in cable tray? For a worst-case example, what if multiple SIS (or any other insulation class) individual conductors were placed in a secondary product (ex. Panduit) that is mounted in the tray. Is there a product on the market or a stipulation in the code that would permit single conductor installations? In many cases, the need for individual conductor wiring (not multi-conductor tray-cable) is necessary and multiple conduit runs are not cost/space effective. Any suggestions?
