Metal actually expands and contracts with weather change, and leaving some small gap in between tray sections is a must. When the distance between the metals is too low, the metals will push against each other and bend. It is important that cable tray installations incorporate features which provide adequate compensation for their thermal contraction and expansion. 1993 NEC Section 300-7 (b) states that “Raceways shall be provided with expansion joints. The Cable Tray Institute is now making available our complete library of technical articles which have appeared in the Cablegram. To determine the number of expansion splice plates you need, decide the length of the straight cable tray runs and the total difference between the minimum winter and. At the point when a cable tray system is utilized as a hardware establishing channel, it is essential to utilize holding jumpers at all development associations to keep the electrical circuit constant. It is significant that cable.
[PDF Version]