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4 PRE-INSTALLATION
4.5 Set-Up
Examine cable trays, trapeze support systems, and other
support systems for acceptability prior to pulling activities.
Install permanent supports properly to ensure the rigidity
of the cable tray, trapeze, or other support system so that
neither the support system nor the cable will be subjected
to damage during the pulling process.
Before installation, verify that the cable(s) can be installed
according to the designed routing and minimum bending
radius requirements.
Where it is not practical to completely remove the cable
from the reel, set up the reel using sheaves or pulleys as
shown in Figure 7 on page 14. The first sheave must be
installed at a point higher than the support system. Use
a roller at the entry and exit points of the tray / trapeze
system. The setup should ensure that the cable is not
kinked or bent beyond the minimum pulling radius (see
Table 2, page 18) or subject to excessive twisting force.
Minimize the amount of tension necessary to pull a cable
as follows:
•
Pull in the proper direction. Where practical, a cable pull
should begin nearest the end having the least degrees
of bends and exit the end having the greater degrees
of bends if at all possible. Also, in vertical sections, an
upward pull is preferred.
•
Minimize the number and degrees of bends the cable
is pulled around under tension. Accomplish this by
finding the straightest route possible using the least
amount of bends.
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