ACSR/Tp, ACSR Twisted Pair Conductor (ASTM B 911)

ACSR/TP, ACSR Twisted pair conductor (ASTM B 911)
Product Features
ACSR TP is a twisted pair of conductors that are wound in a left hand direction on 9 foot intervals in accordance with ASTM B-911. The twisted construction has over three decades of proven field experience in reducing galloping due to the formation of ice on the conductor. The constantly changing profile of the figure eight shape provided by ACSR TP disrupts the lift forces that cause violent elliptical motion of single conductors under ice formation. Twisted pair conductors also exhibit a rocking motion under wind conditions that translate vibration energy into heat, thus providing a self-damping mechanism. ACSR TP has been shown as the most cost effective means to mitigate galloping, Aeolian vibration, and subconductor oscillation. The inherent self-damping mechanism of ACSR TP allows the conductor to be installed per NEC Code limits, thus reducing sag and structure height or allowing for longer ruling spans.

Specifications
ACSR TP is manufactured in accordance with ASTM B-911 Standard Specification for ACSR Twisted Pair Conductor (ACSR/TP) and ASTM B-232 Standard Specification for Concentric-Lay-Stranded Aluminum Conductors, Coated-Steel Reinforced (ACSR). For ACSR TP conductors that have equal area and the same aluminum to steel ratio of a single conductor ACSR, the wind loads will be approximately 16% greater and the ice weight 14% greater.

Stringing Considerations:

The bullwheel should be a minimum of 35x the conductor OD to the bottom of the groove.
The sheave groove radius should be a minimum of 0.55x the conductor OD.
The sheave should be at least 14x the conductor OD to the bottom of the groove.
For Twisted Pair (TP) conductors, the OD in the above guidelines is 2x the OD of an individual conductor.