Why ACCC® Conductor is Used Extensively in Cold Climates

1. Why ACCC® Conductor is Used Extensively in Cold Climates www.ctcglobal.com May 2021

2. Introduction The ACCC InfoCore™ System reduces real-world conductor installation risk experienced by utilities, contractors and lineman across the globe. The ACCC InfoCore™ System can confirm the integrity of the conductor in minutes. While not mandatory, this capability serves to improve reliability and confidence. The system is capable of confirming very long continuous spans and is currently being utilized globally. www.ctcglobal.com

3. ACCC® Conductor History  www.ctcglobal.com Developed initially to improve the performance and longevity of military structures, composite materials have been widely deployed in other demanding applications subject to extreme environmental conditions  – ranging from cryogenic storage vessels to pipelines, offshore oil platforms, rocket nozzles and modern aircraft.  The ACCC® Conductor (“Aluminum Conductor Composite Core”) leveraged the attributes of hybrid carbon and glass fiber composites to improve the performance of bare overhead conductors and is definitely a conductor for extreme weather conditions.

4. Classification The ACCC® Conductor is generally classified as a “High-Temperature, Low-Sag” (HTLS) or “High-Capacity, Low-Sag” (HCLS) conductor. While other conductors such as Invar, GAP, ACCR and ACSS fall within this category due to their abilities to also operate at high temperatures under high load conditions, the ACCC® Conductor offers the lowest thermal sag and greatest operating efficiency – with proven reliability. ACCC® Conductor core is produced to ASTM Standard B987/B987M – 14. www.ctcglobal.com

5. Cold Weather Performance As temperatures drop, line tension increases. This is due to the relatively high coefficient of thermal expansion (“CTE”) of a bare overhead’s constituent materials. While the CTE of aluminum is 23 x 10-6 per degree C, and steel is 11.5 x 10-6 per degree C, the CTE of the ACCC conductor’s composite core is only 1.6 x 10-6 per degree C. Thus the ACCC® Conductor’s core tension fluctuates very little between extreme temperature swings that can range from -60 to over +200°C. A substantial discussion about this can be found in Section 2.8.6 “Engineering Transmission Lines with High-Capacity, Low-Sag ACCC® Conductor” www.ctcglobal.com

6. Heavy Ice Loads When substantial amounts of ice accumulates on bare overhead conductors tension increases due to the added weight. Sag also increases as the added weight causes the conductor’s aluminum strands and core to stretch. While metals will plastically deform and yield under extreme load conditions, the ACCC® Conductor’s composite core is fully elastic and will return to its initial length without permanent deformation. While the outer aluminum strands will yield and plastically deform, the net impact is simply that the thermal knee-point is reduced – which further improves thermal sag. Many of CTC’s partners produce conductor with high strength aluminum alloys that can be incorporated into ACCC conductor designs to accommodate any given requirements. CTC’s application engineering team stands ready to assist. www.ctcglobal.com

7. Cold Climate Installations To date, more than 1000 projects of ACCC® Conductor have been installed in 60 countries. The very first energized ACCC® installation took place in Niagara Falls, New York. While this was considered a trial line, the line remains energized today and has experienced a number of record setting ice storms since it was first installed without issue. A number of other cold climate installations have been completed in North America, China, Russia, and throughout Europe.  www.ctcglobal.com

8. Contact Us  Website: www.ctcglobal.com Phone: +1 949 428 8500 Fax: +1 949 428 8515 Email: info@ctcglobal.com Thank You