Mixing Voltages in Cable Tray

quantum

Senior Member
Location
LA
Since cable tray is not defined as a raceway, would NEC 300.3(C)(1) still apply to cables in the tray system? 392.20(A) is pretty generic in stating that all multiconductor cables operating at 1000V or less can be installed in the same tray. However, 300.3(C)(1) is more strict requiring the insulation of all cables in a raceway to have no less than the applied voltage.

Scenario 1 - Could PLTC (300V) and TC (600V) cables be present in the same tray with no barrier if the highest applied voltage is 480V?
Scenario 2 - Could MC (600V) and MC (300V) cables be present in the same tray with no barrier if the highest applied voltage is 480V? In this case, the 300V rated MC would be industrial CAT6.

I've always assumed 300.3(C)(1) still applies, but I'm second guessing myself.
 

Elect117

Senior Member
Location
California
Occupation
Engineer E.E. P.E.
Cable tray is not a raceway. See Art. 100 definition of raceway.

NEC 392.20 is the section you should be referencing for the scenarios. It is only relevant to separate voltages over 1000V in a cable tray.
 

quantum

Senior Member
Location
LA
Cable tray is not a raceway. See Art. 100 definition of raceway.

NEC 392.20 is the section you should be referencing for the scenarios. It is only relevant to separate voltages over 1000V in a cable tray.
Thanks for the feedback. Hopefully a few others chime in as well.
 
Top