Topic:"Right Of Way" in M12696

Attachment 1: Assessment of Labrador Island Transmission Link (LIL) Reliability in Consideration of Climatological Loads NSPML 2026 Holdback Mechanism BW IR-15 Attachment 1 Page 6 of 134

AI summary This document is an attachment related to the assessment of the Labrador Island Transmission Link (LIL) reliability, considering climatological loads. It is part of the NSPML 2026 Holdback Mechanism and includes an information request (BW IR-15).

In addition to reducing the ice loads on the towers, there are several other advantages specific to this option. Any required repairs to the electrode conductor or structures are made easier due to the smaller structure size of the wood po...

AI summary This text discusses the advantages and disadvantages of a specific option for reducing ice loads on towers. Advantages include easier repairs and less ice accumulation on lower electrode conductors. Disadvantages involve the need for a new right of way, potential conflicts with infrastructure, and the inability to address unbalanced ice loads on the OPGW.

Table 1: Tower Types Tower Type Structure Type Insulator Assembly Type Deflection Angle Limit (degree) A1, A2, A3, A4 Guyed Suspension 0–1 B1 Guyed Suspension 0–3 B2 Self-Support Suspension 0–3 C1, C2 Self-Support Dead End 0–30 D1, D2 Self...

AI summary Table 1 outlines different tower types, their structure types, insulator assembly types, and deflection angle limits. It notes that 90% of towers on the L3501/2 line are suspension towers of types A1, A2, A3, A4, B1, and B2.

Failure Description - During a line patrol on March 30, 2024, damage was discovered between structure 1218 and 1228. A - helicopter patrol the next day identified additional damage at structure 1232, and was able to detail the - damage on...

AI summary During a line patrol on March 30, 2024, damage was discovered between structures 1218 and 1228. A helicopter patrol the following day identified additional damage at structure 1232 and detailed the damage on all structures, including bent and failed steel members, conductor damage, and minor pole conductor damage.

Table 2: Summary of Structure and Conductor Damage Crossarm Damage Conductor Damage Pole OPGW Tower EL1 EL2 EL1 El2 Conductor Tower Peak 1216 no no no no no no 1217 no no no no no no 1218 no yes no yes no no 1219 no yes no yes no no 1220 n...

AI summary Table 2 summarizes the damage to structures and conductors across various towers, indicating the presence or absence of damage to crossarms, conductors, poles, OPGW, and tower peaks. The data shows varying levels of damage across different towers, with some towers showing no damage and others showing multiple points of damage.

1 5.1 Failure Location - 2 Structures are numbered sequentially along the line starting at Muskrat Falls. Structure numbers that - 3 sustained damage are str. 1218–1228 and 1232. These structures are located on the south coast of - 4 Labra...

AI summary The failure location involves structures numbered 1218–1228 and 1232, located on the south coast of Labrador, 11–16 km from the nearest highway. These structures are in loading zone 3a and are Type A1 tangent towers with specific attachment heights. The damage occurred in a section with specific wind and ice design loading conditions.

Table 3: Damaged Structure Information Summary Structure Number Structure Type Structure Height Height to Electrode Attachment (m) Height to OPGW Attachment (m) 1218 A1 A1+6.0 33.968 41.05 1219 A1 A1+12.0 39.966 47.05 1220 A1 A1+6.0 33.969...

AI summary Table 3 summarizes damaged structure information, including structure numbers, types, heights, and attachment points. Section 5.2 discusses engineering recommendations for repairs related to these damaged structures.

Table 4: Comparison of Field Damage and Modeling Results for Ice Loading Field Damage Modeling 9 90 mm Modeling 100 mm Crossarm EL Crossarm EL Crossarm Dan nage OPGW Tower Damage OPGW Damage OPGW Tower EL1 EL2 Peak (% Utilization) Tower Pe...

AI summary Table 4 compares field damage observations with modeling results for ice loading on various structures, including towers and crossarms, under different ice thickness scenarios (9 mm and 100 mm). The data includes utilization percentages and damage indicators for specific poles and electrodes.

Table of contents Executive summary ii Figure 1-1: Google map provided by NL Hydro [1] showing the general compass directions of the segments of the transmission lines between Tower #1200 and Tower #1229. The map also shows the reported di...

AI summary The text provides a table of contents with references to figures illustrating transmission line failures, conductor specifications, and analysis of failed components. It includes details about the location of failures, conductor configurations, and images of damaged equipment.

Wayland Engineering Ltd. was asked by Newfoundland and Labrador Hydro (NL Hydro) to conduct an investigation for two electrical conductors (EL-1 and EL-2) removed from suspension Tower #1225. The conductors routed electrical power along th...

AI summary Wayland Engineering Ltd. investigated the failure of two electrical conductors (EL-1 and EL-2) removed from suspension Tower #1225. The failures occurred on March 30, 2024, due to unbalanced ice loads and wind velocities exceeding design criteria. The investigation found significant ice accumulation and wind speeds that exceeded the line's design limits, leading to conductor failures.

Tower No. Description of Damage Sustained by Conductor EL-1 and EL-2 EL1 conductor stripped on 1221 side and birdcaged on 1223 side, EL2 Conductor 1222 complete broken on 1223 side. EL1 conductor stripped on 1222 side and birdcaged on 1224...

AI summary The document details damage to conductors EL-1 and EL-2 at various tower locations, including stripping, birdcaging, and breaking. A map from NL Hydro is referenced, showing the transmission line segments and wind direction associated with the failures.

Wire Strand Diameter Ranges (mm) Outer Aluminum Strands Inner Steel Strands Layer 1 Layer 2 Layer 3 Layer 4 Layer 5 Layer 6 Conductor EL-1 3.40-3.73 3.56-3.73 3.63-3.68 2.06-2.24 2.03-2.11 2.11 Figure 3-2: SEM backscatter image of a repres...

AI summary The document presents a table and image related to the analysis of a failed conductor (EL-1), detailing wire strand diameter ranges and showing a scanning electron microscope (SEM) image of a zinc-coated steel reinforcing strand, highlighting variations in zinc coating thickness.

3.2 Dimensional Characterization of Failed Conductor EL-2 Wire Strands Table 3-2 contains a summary of wire strand diameter ranges for the 6 layers associated with the failed conductor EL-2 (the detailed measurement results have been provi...

AI summary This section provides a dimensional characterization of failed conductor EL-2 wire strands, including diameter ranges for aluminum and zinc-coated steel layers. The measurements are compared to ASTM B-232 specifications. SEM images show zinc coating thickness variations but no breaches to the steel core.

Wire Strand Diameter Ranges (mm) Oute Outer Aluminum Strands Oute er Aluminum Strands Layer 1 Layer 2 Layer 3 Layer 4 Layer 5 Layer 6 Intact Conductor 3.71-3.76 3.71-3.76 3.71-3.73 2.21-2.24 2.21-2.24 2.21 Figure 3-4: SEM backscatter image...

AI summary The text describes a table and an image related to the wire strand diameter ranges of an intact conductor and provides a backscatter image of a zinc-coated steel reinforcing strand, highlighting variations in zinc coating thickness.

Annex B Dimensional Characterization of the Failed Section of ACSR Grackle (Zinc Coated) Conductor EL-1 Table B-1 summarizes the outer aluminum conductor and inner steel reinforcing wire strand diameter measurements for the failed section...

AI summary This annex provides dimensional characterization of a failed section of ACSR Grackle (Zinc Coated) Conductor EL-1, including measurements of the outer aluminum conductor and inner steel reinforcing wire strand diameters, as well as visual examples of zinc coating thickness on the steel strands.

Table B-1: Summary of the outer aluminum conductor and inner steel reinforcing wire strand diameter measurements for the failed section of conductor EL-1. Wire Wire Strand Diameter Ranges (mm) Strand Outer Aluminum Strands Inner Steel Stra...

AI summary This table provides detailed measurements of the outer aluminum conductor and inner steel reinforcing wire strand diameters for the failed section of conductor EL-1. It includes various layers and notes on fused or distorted strands.

Annex C Dimensional Characterization of the Failed Section of ACSR Grackle (Zinc Coated) Conductor EL-2 Table C-1 summarizes the outer aluminum conductor and inner steel reinforcing wire strand diameter measurements for the failed section...

AI summary This annex provides dimensional measurements of the failed section of ACSR Grackle (Zinc Coated) conductor EL-2, including diameter measurements of the outer aluminum conductor and inner steel reinforcing wire strands, as well as figures showing the thickness of the zinc coating.

Table C-1: Summary of the outer aluminum conductor and inner steel reinforcing wire strand diameter measurements for the failed section of conductor EL-2. Wire Wire Strand Diameter Ranges (mm) Strand Outer Aluminum Strands Inner Steel Stra...

AI summary Table C-1 presents the diameter measurements of the outer aluminum conductor and inner steel reinforcing wire strands for the failed section of conductor EL-2. The table includes measurements across multiple layers and notes that some strands were fused or distorted.

NSPML Responses to Industrial Group Information Requests 1 Request IR-10: 12 to previously reported issues of ground potential, which resulted in 13 approximately six weeks of outages. 14 (i)If so, please explain what this "ground potentia...

AI summary The text outlines information requests regarding ground potential issues on the Labrador-Island Link (LIL) that caused outages, including requests for explanations, engineering reports, and the status of remediation. It also asks about the connection between these issues and attempts to increase the LIL's operating capacity and the status of a planned 900 MW capacity test.