Initial or Reelback Tension
The initial or reelback tension is the tension required to pull the cable from the reel while the reel is moving. This tension varies with a number of factors, the most influential being the phase conductor size and weight. However, the amount of cable on the reel, the manner in which the cable is unwound, and the ability of the reel to spin freely all play an important role in determining this value. Due to the virtually unlimited values these factors may assume, it is extremely difficult to accurately predict the initial or reelback tension.
The following table provides a rough estimate of the initial or reelback tension for a specified phase conductor.
|
Phase Conductor |
Reelback Tension (lb) |
|
|---|---|---|
|
Primary Aluminum |
#2, 7 strd AL CN 15 KV XLP #1/0, 19 strd AL CN 15 KV XLP #4/0, 19 strd AL CN 15 KV XLP 3-750, KCM, 61 strd AL 15 KV XLP w/ #4/0 bare CU neut 3-1000 KCM, 61 strd AL 15 KV XLP w/ #4/0 bare CU neut |
50 50 60 0* 0* |
|
Primary Copper |
all PILC cable |
0* 0* 0* |
|
Secondary Aluminum |
#1/0, 19 strd AL 600
V XLP & triplex |
40 40 45 45 50 50 |
|
Secondary Copper |
#2, 7 strd CU 600 V
XLP |
45 45 50 50 55 55 60 |
* A motorized reel must be used because of the cable weight.