approved threaded couplings may be secured as shown in table 5-5, provided such fastening prevents transmission of stress to terminations when conduit is deflected between supports.
Table 5-5. - Spacing of Rigid-Metal Conduit Supports
CONDUIT SIZE | RIGID-METAL SUPPORT |
(INCHES) | (FEET) |
1/2 and 3/4 | 10 |
1 | 12 |
1-1/4 and 1-1/2 | 14 |
2 and 2-1/2 | 16 |
3 and larger | 20 |
A variety of conduit hangers and supports and several applications are shown in figure 5-21. U-channel supports are ideal for supporting several runs of conduits. In laying out these supports, consideration should be given to future conduit runs as well as those to be installed initially. It is a simple matter to provide U-channels or trapeze hangers with additional space for future conduits. This procedure greatly reduces the cost of installing new conduit at a later date. With the U-channel system, as shown in figure 5-21, special clamps are slipped into the channel slot, and the top bolt of the clamp securely fastens the conduit to the U-channel.
The U-channel can be directly fastened to a wall or ceiling, or it can be attached to bolted threaded rod
Figure 5-21. - Common conduit supports.
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