Kinectrics North America Inc. Report No.: K RC-0002-R00. October 2, Zsolt Peter Transmission and Distribution Technologies Business

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1 To: CTC Global 2026 McGaw Avenue Irvine, CA 92614, USA THERMO-MECHANICAL CYCLE TEST ON 540 mm 2 ACCC/TW CONDUCTOR Kinectrics North America Inc. Report No.: K RC-0002-R00 October 2, 2013 Zsolt Peter Transmission and Distribution Technologies Business 1.0 INTRODUCTION A Thermo-Mechanical Cycle Test was performed on a sample of inch (28.15 mm), 540 mm 2, Dublin, Aluminum Conductor, Composite Core/Trapezoidal Wire (ACCC/TW) conductor for CTC Global Corporation (CTC). The Dublin/Drake (Dublin is the metric size equivalent to Drake in US customary units) conductor consists of a single composite glass and carbon fiber core covered by two (2) layers of twenty two (22) annealed, trapezoidalshaped aluminum alloy wires. The specification for the conductor is shown in Appendix A. The ACCC/TW Dublin/Drake conductor successfully met all requirements of the test protocol developed by EPRI and in accordance with GIGRE 426, Section 4.17, Temperature Cycle Test methods. The test consists of five hundred (500) thermo-mechanical cycles and five (5) holds at 70% of the conductor s rated tensile strength (RTS) at room temperature. The maximum test temperature during the thermo-mechanical cycles was approximately 200 C measured on the surface of the test conductor. Sufficient length of test conductor and dead-end assemblies were received on April 16 th, 2013 in good condition from CTC Global. The test was performed from April 25 th through August 1 st, 2013 in accordance with a proposed test procedure described in CIGRE Guide 426, Section 4.17, and in accordance with Kinectrics ISO 9001 Quality Management System. Two (2) conductors were tested: one tensioned test conductor and one non-tensioned dummy conductor. Both tensioned and dummy conductors used standard field rated deadends for electrical and mechanical connection throughout the thermo-mechanical cycling. At the end of the cycling test, breaking load tests were performed on both conductors to assess the remaining tensile strength. Both conductors were pulled apart well above the conductor s Rated Tensile Strength with the test conductor reaching 111.6% of conductor s RTS and the dummy conductor reaching 112.3% of conductor s RTS. PRIVATE INFORMATION Contents of this report shall not be disclosed without authority of the client. Kinectrics North America Inc., 800 Kipling Avenue, Toronto, Ontario, M8Z 5G5

2 2.0 TEST OBJECTIVE AND STANDARD The primary objective of the Thermo-Mechanical Cycle Test was to subject a CTC glass/carbon fiber composite core HTLS (high-temperature low-sag) conductor to thermal and mechanical loads simulating those encountered in actual operation. The test protocol was based on a proposed test procedure described in CIGRE Guide 426, Section 4.17, Temperature Cycle Test. However, no industry explicit test standard is available for evaluating the combined effects of thermal and mechanical cycles on HTLS conductors. 3.0 TEST SET-UP 3.1 Test Conductors The selected conductor size for the test was inch (28.15 mm), 540 mm 2, Aluminum Conductor, Composite Core/Trapezoidal Wire (ACCC/TW) Drake/Dublin conductor. The Conductor is produced by LAMIFIL in Belgium and has the reel number LAM 384 and has a core reel number The conductor consists of a single composite glass and carbon fiber core covered by two (2) layers of twenty two (22) annealed, trapezoidal-shaped aluminum alloy wires. The composite core is manufactured by CTC Global (CTC) from California (USA) and the conductor is stranded by Lamifil N.V., from Belgium. The complete specification for the conductor is shown in Appendix A. CTC supplied a sufficient length of conductor in good condition for testing. Two (2) approximately 47.5 ft (14.5 m) lengths of conductor were cut from the supplied reel. One conductor was used in the tensioned span, and the second one served as a dummy return conductor. All conductor ends were terminated with Burndy high temperature dead-end connectors, P/N The effective conductor length between the dead-end assemblies was approximately 42.5 ft (13 m). The compression connectors, manufactured by Burndy, were installed by Chris Wong of CTC with the assistance of Peter Chan from Burndy and KNAI personnel. CTC also provided appropriate compression dies, and KNAI supplied a 60-ton press for the installation. The mouth of each dead-end assembly was marked with orange paint to permit tracking of any conductor slip. Porcelain insulators were connected to each compression dead-end in order to electrically isolate the energized test conductors from the rest of the test setup. 3.2 Test Apparatus The test was carried out in Kinectrics Mechanical Testing Laboratory. Three (3) tests were performed: i) Thermo-Mechanical Cycling Test, ii) Sustained Load Test at 70% RTS (Rated Tensile Strength), iii) Breaking Load Test to measure the remaining tensile strength of the test assembly. Page 2 of 17 K RC-0002-R00

3 i) Thermo-Mechanical Cycling Test Figure 1 provides the test setup schematics. A photo taken from the actual test setup is shown in Figure 2. A test machine having a load accuracy of ± 2% was used for this test. The test conductor was loaded using a hydraulic piston on one end and a cantilever beam weight system on the opposite end. The conductor was located in a thermally isolated box in order to assure thermal stability and consistency between thermal cycles, but the compression dead ends were located outside the heated part of the isolated box. The thermally isolated box was equipped with five (5) large industrial fans. The fans were switched on during the cooling cycles in order to shorten the cooling period by forced convection. A dummy conductor running in parallel to the test conductor under tension, was also installed in order to measure conductor temperature at various locations. The dummy conductor was not under tension, but passed through the same current and underwent the same temperature cycles as the test conductor. The dummy conductor was also used as the return conductor to the power transformer. An AC current transformer and a contactor provided necessary current to increase the temperature in the conductor to the desired temperature. The AC current transformer supplied the current in the test conductor through jumper terminals that were attached to the test conductor with compressed dead-ends. ii) Sustained Load Test at 70% RTS This test was performed using the same test setup as the Thermo-Mechanical Cycling Test. At the end of the Thermo-Mechanical Cycling Test, the cantilever tray was loaded with additional weight and the hydraulic piston was used again to increase the tension to 70% RTS. iii) Breaking Load Test on Compression Dead-end Connectors This test was performed at the end of the five hundred (500) thermo-mechanical cycles and five (5) holds at 70% RTS. On completion of the Thermo-Mechanical Cycling Test, the test and dummy conductors were cut at the center span and only half of the span length was used for Breaking Load Test. The half-length of the conductor used for testing was prepared by bonding the cut end of the conductor into tensioning grips. The remaining half length of test and dummy conductors was sectioned and sent back to CTC Global for further evaluation. The dummy and test conductor samples were installed in a hydraulically-activated horizontal test machine and individually tested. The pin-to-pin distance between the compression dead-end connector and epoxy resin dead-end loading point was approximately 7.55 m, while the effective conductor length was approximately 6.2 m. A schematic of the test set-up is shown in Figure 3. Page 3 of 17 K RC-0002-R00

4 3.3 Instrumentation Conductor Tension for Thermo-Mechanical Cycling and Sustained Load Test at 70% RTS A strain gauge load cell (see Appendix B) measured the tension in the test conductor at the north end of the test span during the test. The load cell was installed between the insulator and the dead-end structure so that it would be electrically isolated from the conductor. The signals from the load cell were amplified to provide a 0 to 5 V signal for the data acquisition system (see Appendix B). Temperature Measurements A total of twenty-seven (27) thermocouples were located on the conductors, dead-end and jumper terminal compression connectors. The temperature of the conductors was measured at multiple locations (see Figure 4) along the length of the conductors. Six (6) thermocouples were placed in outer strands of each test conductor and dummy return conductor to monitor surface temperature of the conductors. Three (3) additional thermocouples were placed in the dummy return conductor: i) in the composite core at the center of the test span; ii) in the composite core 1.5 m north from the center; and iii) between first and second aluminum layers near center of the test span. Ambient temperature was measured at two (2) locations: near the south end and near the north end of the isolated test box. Glass isolated thermocouples of J-type were used to measure the temperature of the conductors. All thermocouples were electrically isolated from other instrumentation to prevent electrical interference into the data acquisition system. Conductor Tension for Breaking Load Test A load cell located at the hydraulic end of the sample measured the tension. The data logging rate during loading was a minimum of every ten (10) seconds. 3.4 Control of Current in Loop and Data Acquisition The data acquisition system (DAQ) recorded the conductors temperature and tension, and controlled the contactor. The data were sampled and recorded periodically (typically every 2 minutes). Continuous AC current of ~1440 amperes was circulated in the conductors. A closed-loop system was used to maintain the target temperature of the test conductor. The data acquisition system (DAQ) recorded the maximum outer temperature of the tensioned and non-tensioned conductors and controlled the motor-driven variac. The variac varied the supply voltage to the current transformer. The target test current was slightly adjusted (using a variac) to maintain the maximum outer temperature of the conductor at 200 C ±5 C. The controller instructed the transformer to shut off and wait, if any thermocouple readings were higher than 210 C. Page 4 of 17 K RC-0002-R00

5 4.0 TEST PROCEDURE It is intended to subject the test conductor to a total of 500 thermo-mechanical cycles and 5 holding periods at 70% RTS for 24 hours. The conductor tension of 20% (± 2%) of the conductor s RTS at ambient temperature is chosen for the thermo-mechanical cycling test. The cantilever weight system allows a decrease in tension to occur during the hightemperature range of the cycling test to simulate the expected field tensions. 20% RTS is considered an upper limit for tension at extreme conductor temperatures. Sustained Load Test at 70% RTS hold for 24 hours is intended to simulate high wind and/or ice conditions. The test was carried out according to the following test procedure: i) The conductor in the thermally isolated box at room temperature is tensioned to approximately 20% of the rated tensile strength (corresponds to 8260 lb or kn). This initial tension is allowed to change ±2% RTS during the test due to ambient temperature variations. The percentage variation corresponds to tensions from 7430 lb to 9090 lb (33.1 kn to 40.4 kn). The entrance of tensioned dead-end connectors is marked with paint to monitor conductor slip after the conductor is brought to 20% RTS. ii) 100 thermo-mechanical cycles are applied on the test conductor from room temperature to 200 C ± 5 C maximum conductor temperature measured in the outer layer of the test conductor. Each thermo-mechanical cycle is performed as follows: A. Starting at room temperature (nominally 20 C - 30 C), the temperature in the conductor is increased by circulating a constant alternating current (AC) supplied by a current transformer. B. The data logger monitors temperatures along the length of test and dummy conductors at various locations and records data every two (2) minutes. The highest value of all thermocouples readings measured in outer layer of tensioned and non-tensioned conductors is selected and logged as maximum outer temperature. The target test current was slightly adjusted (using a variac) to maintain the maximum outer temperature of the conductor at 200 C ± 2.5 C. C. After 10 min heating period, the controller instructs the transformer to shut off. Industrial fans are switched on automatically to cool the conductors and connectors by forced convection to the ambient temperature. D. After the conductors and all connectors are cooled to, and stabilized, at room temperature (within ± 5 C), the fans are switched off and the transformer is switched on. E. The cycle is repeated for accumulating total of hundred (100) cycles. After all hundred (100) cycles are completed, the controller instructs transformer to shut off. iii) On completion of one hundred (100) thermo-mechanical cycles, the electrical connections were removed. The test conductor was then tensioned to 70% RTS by placing additional weights on the cantilever tray. This tension was maintained for twenty four (24) hours. The data acquisition system (DAQ, see Appendix B) recorded the conductor tension periodically. On completion of the 24 hour hold period at 70% Page 5 of 17 K RC-0002-R00

6 RTS, the load is reduced to 20% RTS gradually and the compression dead-ends are inspected for any slippage or movement. iv) Steps from i) to vi) are repeated four (4) more times (for a total of five (5) times). v) At the end of the test, the test and dummy conductors were cut in the middle separating the conductors into two (2) equal sections. One (1) half of each conductor (dummy and test) was sent to CTC Global for further evaluation. vi) The remaining half sections of dummy and test conductors were re-terminated with epoxy resin dead-ends. Therefore, both conductors (test and dummy) had one (1) compression dead-end on one end, and one (1) epoxy resin dead-end on another end. The Breaking Load Test was performed on the remaining parts of the test and dummy conductors. 5.0 TEST RESULTS AND DISCUSSION Thermo-Mechanical Cycling Test A typical thermo-mechanical cycle is shown in Figure 5 for the test conductor. During the first 100 thermo-mechanical cycles the tensioned test conductor and non-tensioned dummy conductors had very similar temperatures. Due to the end effects of the test setup, the temperature close to the thermal barriers at south and north ends was about 10 C lower. After the first 70% RTS hold period (first 100 thermo-mechanical cycles), the test conductor had some loosened outer strands (due to high tension and annealed aluminum) while no loosened aluminum layer could be observed for non-tensioned dummy conductor. This resulted in test conductor temperatures to be slightly lower than dummy conductor temperature. After each 70% RTS loading period more slack was introduced to the test conductor due to elongating annealed aluminum wires under high tension. Significantly less loosened aluminum wires were noticed on the dummy conductor (see Figure 6). Conductor Breaking Load The following observations were made with regards to the Breaking Load Test: i. After 500 thermal cycles (no load applied) the aluminum wires of the dummy conductor sample before starting the Breaking Load Test were loose, but this loosening disappeared once the tension reached ~30% RTS. ii. The dummy conductor (non-tensioned during Thermo-Mechanical Cycling Test) breaking load was at 46,359 lb which corresponds to 112.3% of conductor s RTS. The dummy conductor broke near the middle of the test assembly. iii. After 500 thermo-mechanical cycles the aluminum wires of the test conductor sample were also loose before starting the Breaking Load Test. It was noticed that the strands settled in and loosening disappeared once the tension exceeded ~70% RTS. iv. The test conductor (tensioned during Thermo-Mechanical Cycling Test) breaking load was at 46,089 lb which corresponds to 111.6% of conductor s RTS. This breaking load was very close (within 1%) what was measured for the non-tensioned dummy conductor. This result indicates no degradation in strength of conductor, as tested, occurred as a result of the Thermo-Mechanical Cycling. Page 6 of 17 K RC-0002-R00

7 All work was performed by Kinectrics North America Inc. personnel at 800 Kipling Avenue, Toronto, Ontario, M8Z 5G5, Canada, under CTC Global Corporation s Purchase Order No A copy of Kinectrics ISO 9001 Accreditation Certificate is included in Appendix C. ZsP:PF:MK:AR:CP:JC DISCLAIMER Kinectrics North America, Inc (KNAI) has taken reasonable steps to ensure that all work performed meets industry standards as set out in Kinectrics Quality Manual, and that, for the intended purpose of this report, is reasonably free of errors, inaccuracies or omissions. KNAI DOES NOT MAKE ANY WARRANTY OR REPRESENTATION WHATSOEVER, EXPRESS OR IMPLIED, WITH RESPECT TO THE MERCHANTABILITY OR FITNESS FOR ANY PARTICULAR PURPOSE OF ANY INFORMATION CONTAINED IN THIS REPORT OR THE RESPECTIVE WORKS OR SERVICES SUPPLIED OR PERFORMED BY KNAI. KNAI does not accept any liability for any damages, either directly, consequentially or otherwise resulting from the use of this report. Kinectrics North America Inc., Page 7 of 17 K RC-0002-R00

8 Figure 1: Typical Test Setup for Thermo-Mechanical Cycling Test (Current Supply not shown) Test Conductor Dummy Conductor Figure 2: Photo of Tensioned Conductor and Dummy Conductor Installed in Insulated Box for Thermo-Mechanical Cycling Page 8 of 17 K RC-0002-R00

9 Figure 3: Schematics of Test Setup for Breaking Load Test Figure 4: TC Map of Thermo-Mechanical Cycling Test Page 9 of 17 K RC-0002-R00

10 Figure 5: Typical Thermo-mechanical Cycle on Test Conductor before the First 70% RTS Loading Test Conductor Dummy Conductor Figure 6: Condition of Test and Dummy Conductors after Thermo-Mechanical Cycling Test Page 10 of 17 K RC-0002-R00

11 APPENDIX A DATA SHEET FOR 540 mm 2 ACCC/TW DUBLIN CONDUCTOR RECEIVED FROM CTC GLOBAL Page 11 of 17 K RC-0002-R00

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14 ISO-9001 Form: QF11-1 Rev 0, APPENDIX B INSTRUMENT SHEET (Ref. Thermo-Mechanical Cycling Test on Dublin, ACCC/TW Conductor) Thermo-Mechanical Test on Dublin, ACCC/TW Conductor Test Start Date: April 16, 2013 Test Description: Project Number: K Test Finish Date: August 1, 2013 TEST DESCRIPTION EQUIPMENT DESCRIPTION MAKE MODEL ASSET # or SERIAL # ACCURACY CLAIMED CALIBRATION DATE CALIBRATION DUE DATE TEST USE Page 14 of 17 K RC-0002-R00 Thermo- Mechanical Cycling Test Breaking Load Test Data Logger Load Cell Load Conditioner Current Transformer Current Transducer National Instrument Aries Daytronics PCI-6221 FTU-B K ( 60k lbs) 3170 KIN # ±0.1% of ±1% of July 20, 2012 July 20, 2013 Data Acquisition April 16, 2012 April 16, 2014 Tensile Load Flex Core KIN ±0.3% FS June 28, 2012 June 28, 2014 Electrical Current Flex Core ACT-005-CX5 KIN Sept. 19, 2012 Sept. 19, 2013 Electrical Current Thermocouple Omega Type J (30AWG) KIN Thermocouple Omega Type J (30AWG) KIN ±1% of ±1% of Sept. 21, 2012 Sept. 21, 2013 Temperature July 5, 2012 July 5, 2013* Temperature Digital Caliper Mitutoyo CD-6 CSX KIN mm July 9, 2012 July 9, 2013 Conductor Diameter Measuring Tape Stanley FatMax (34-813) KIN Load Cell (MTS) Conditioner Data Logger Lebow MTS National Instrument 3156 (100,000 lbs) DC PCI KIN KIN Measuring Tape Stanley FatMax (34-813) KIN Temperature Transmitter Thermocouple *1 month extension awarded Omega TX-13 Type T KIN KIN < 0.05% of ±1% of ±0.1% of < 0.05% of ±1% of November 30, 2012 November 30, 2014 Conductor Length October 11, 2012 October 11, 2014 Conductor Tension January 11, 2012 January 11, 2014 Data Acquisition November 30, 2012 November 30, 2014 Conductor Length September 15, 2012 September 15, 2014 Temperature

15 APPENDIX C KINECTRICS ISO 9001 QUALITY MANAGEMENT SYSTEM REGISTRATION CERTIFICATE Page 15 of 17 K RC-0002-R00

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17 DISTRIBUTION Mr. Eric Bosze (1) CTC Global 2026 McGaw Avenue Irvine, CA USA Mr. Zsolt Peter (1) Kinectrics North America Inc., Unit Kipling Ave, KB 223 Toronto, Ontario M8Z 5G5 Canada Page 17 of 17 K RC-0002-R00