Pulling tension – CommScope Trunk & Distribution Cable User Manual
Page 43
Pulling Tension
Pulling tension for CommScope cable types are shown in this chart.
NEVER EXCEED THE MAXIMUM PULLING TENSION.
Excessive forces applied to the cable will cause the cable to permanently
elongate. Good construction techniques and proper tension monitoring
equipment are essential. The highly flexible nature of QR cable makes it
very difficult to exceed the maximum pulling tension.
Tail loading is the tension in the cable caused by the mass of the cable
on the reel and reel brakes. Tail loading is controlled by two methods.
It can be minimized by using minimal braking during the pay-off of the
cable from the reel - at times, no braking is preferred. Tail loading can
also be minimized by rotating the reel in the direction of pay-off.
Break-away swivels should be placed on each cable to ensure that the maximum
allowable tension for that specific cable type is not exceeded. The swivel is placed
between the cable puller and pulling grip. A break-away swivel is required for each
cable being pulled.
Dynamometers are used to measure the dynamic tension in the cable. These
devices allow continuous review of the tension and accordingly a realization can be
made of any sudden increase in pulling tension.
Cable
Max. Pulling Tension
lbs / kgf
QR 320
120 (54.5)
QR 540
220 (100)
QR 715
340 (154)
QR 860
450 (204)
P3 500
300 (136)
P3 625
475 (216)
P3 750
675 (306)
P3 875
875 (397)
MO500
270 (123)
MO650
360 (164)
MO750
500 (227)
QR’s flexible
construction
means
longer runs
and more
45°/90° bends
are possible
Underground Installation
5.2
Pulling Tension