ABSTRACT. When assessing the long-term reliability of ADSS cables placed on high voltage power structures, environmental effects of EMF voltage, UV ...
High Voltage ADSS Reliability Modeling: Environmental and Climatological Effects on Advanced Jacket Material Selection William DeWitt, Swati Neogi, Brian G. Risch**, Pierre Coat, Danny Ammons, George Karady* and Johnny Madrid* Alcatel OFCCC, Claremont, NC *Arizona State University, Department of Electrical Engineering, Tempe, AZ
**To whom correspondence should be addressed. dissipate the electrical phenomenon.1,2
ABSTRACT When assessing the long-term reliability of ADSS cables placed on high voltage power structures, environmental effects of EMF voltage, UV radiation, temperature extremes, humidity, salt and pollution need to be examined to determine which type of jacket material should be used. This paper examines results of extensive materials aging and dry band arc testing conducted on ADSS cables with varying jacket materials in order to determine the relative importance of these environmental factors, and how combinations and interactions of these effects influence the degradation of cable jacket materials.
that
causes
the
Dry band arcing is a completely different phenomenon that has proven to be a more elusive problem to solve and is the subject of this paper. Events leading to dry-band arcing can be described as follows. When first installed, the outer jacket of an ADSS cable is hydrophobic and non-conductive. As a result, its resistance is very high even when wet. Over time, however, it becomes hydrophilic and in some environments, significant contamination may accumulate. During wet conditions the contamination layer can become conductive and capacitively coupled currents from adjacent energized conductor’s flow within this layer. As the contamination dries, narrow bands form. These bands can have high voltages across them, enough to cause arcs to occur across the dry band. If the current available to the arcs is high enough (i.e. the resistance of the contamination is small enough to allow pre dry-band currents in the milliampere range) arc heating can degrade the ADSS jacket and cause cable failure.3
This paper correlates climatological factors in addition to the EMF system configuration into reliability guidelines. World maps of climatological data and pollution levels are surveyed in order to estimate how these factors can lead to variability in cable lifetime and reliability. Finally, climatological data is combined with materials aging data and electrical test results to present improved guidelines for assessment of long term robustness of cable networks. INTRODUCTION All Dielectric self-supporting (ADSS) fiber optic cable offers a rapid and economical solution for utility and telecommunication companies to deploy optical fiber cables along existing electric and telephone utility pole rights of way assets. ADSS cables offer an alternative solution over other aerial application cables such as lashed or Figure-8 cables. All dielectric solutions are preferred and sometimes mandatory for installation in or near electric power lines on utility structures where cables containing metallic elements are not advised.
Selection of the proper cable jacket material is very important to guarantee the long-term reliability of the cable. This selection depends upon the phase to phase voltage of the power utility system, the environment, and the position of the ADSS cable within the electrical field. In very low field voltage environments, a typical high-density polyethylene (HDPE) material is used. However, in higher field voltage special track resistant jacket material is required to prevent the dry band arcing caused by proximity to high voltage lines. Cross-linked or filled thermoplastic materials have shown the best resistance to electrical activity. Previous research has shown that filled thermoplastic jacket materials containing approximately 2.5% carbon black provide a superior combination of electrical and mechanical properties for protection of the cables. 4
When ADSS optical fiber cables are installed in close proximity to high voltage power lines, two electrical phenomenons known as dry band arching and corona have caused premature failure of cables. Corona is caused by high electric field gradients at the tips of the suspension hardware and has been observed in both field and laboratory environments. While corona can be very damaging to the cable, mitigation devices exist. When properly installed at each attachment point, these devices
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A thermoplastic track resistant jacket with acceptable carbon black content provides a three pronged solution to dry band arcing. First, the addition of carbon black ensures the ADSS will be resistant to UV aging, thus reducing collection of salt/pollution on cable sheath subsequently 337
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lowering the cable resistance. Second, properly selected filled thermoplastic jacket materials minimize carbon surface tracking better than cross-linked materials. This assures a high electrical stability of the cable jacket. Finally, the filled thermoplastic track resistant jacket is resistant to heat damage by ablation (vaporization of material resulting in pitting), should arcing occur5,6. A filled thermoplastic also provides similar abrasion resistance to HDPE jacket material.
Effect of Aging on Mechanical Performance of the Outer Cable Jacket Four cables with different outer jacket materials were subjected to heat and moisture aging and UV aging conditions. Heat aging had been done at 85oC and at 85% relative humidity for 30 days. Heat aged as well as virgin cables were subjected to UV aging according to the IEC standard 68-2-5. Procedure C of the standard has been followed and the duration of the test was 10 days. The total UV dose received during the 10 Day UV test was 220 KWh/m2 or (792 MJ/m2). The test temperature was kept constant at 50°C. Mechanical properties such as the tensile strength and the elongation of the outer cable jacket after aging were measured according to the method FOTP 89 and compared with that of the unaged outer cable jacket. An Instron model 4202 was used for tensile measurement.
Some consider a Mid Span Space Potential of 12-25 kV as the standard threshold for specifying special jacket materials for ADSS cable7,8, but a previous study “Continued investigations of ADSS designs and reliability considerations with respect to field voltage tracking, and cable installation practices,” IWCS Proceedings 1997, concluded that without further protection, cable jackets prematurely failed at this threshold voltage.3 Other factors also need to be considered such as climate, pollution level, wet/dry cycles etc.
Table 1: Composition of Cable Jacket Materials. Cable A HDPE Cable B Filled Thermoplastic/ High Filler Cable C Filled Thermoplastic/ Low Filler Cable D Unfilled Polyolefin Compound
EXPERIMENTAL The cables tested were of a similar construction in which Polybutylene Terapthalate (PBT) tubes containing optical fibers were stranded around a central strength member. Superabsorbent waterblocking materials were used to make the interstices between the tubes watertight.9 The inner core was surrounded by an inner sheath made of Medium Density Polyethylene (MDPE). Between the inner sheath and outer sheath aramid strength yarns were applied. The material of the outer sheath was varied in order to examine the effects of environmental exposure and electrical testing as a function of outer jacket material. Various outer jacket materials were investigated in this study as well as earlier studies3,4,5,8 to get a complete representation of all common, commercially available jacket materials. A diagram of the cable construction is shown in Figure 1. Details of outer jacket material and are outlined in Table 1.
Effect of Dry Band Arcing Effects of dry band arcing on the performance of both dry and flooded ADSS cable jackets were studied by subjecting the cables to electrical field voltage before and after aging. Two test methods were compared in order to give correlation between different test methodologies. A standard salt-fog test as well as an alternative accelerated electrical test was performed on filled thermoplastic trackresistant jacketing compounds and HDPE. The accelerated test method was performed on all materials. The design of electrical experiments and details of the test methods are described below. Salt-Fog Testing Salt Fog testing was performed on unaged and aged cables according to IEEE P1222 Draft March 1997 - Annex A. Each cable sample was sealed at both ends and attached to a high voltage brass ferrule on one end and a grounded cable dead end on the other. The samples were then placed under tension and put into the salt fog chamber. A 1% NaCl (salt) solution was dispensed at a constant rate of 0.4 liters per cubic meter per hour. After the system was energized at 30 kV, the cables were inspected at 50 hours, 100 hours and then every 100 hours there after. Values of the parameters used in salt fog test are listed below.
Figure 1. Schematic Representation of the Cross Section of Typical ADSS Cable.
Ripcords PBT Tube Central Strength Member Optical Fibers Aramid Strength Yarns Water Blocking Material PE Jackets
Duration of the test: Test Voltage: Temperature: Flow rate: NaCl content: Particle size:
The track-resistant materials used in this study were specially formulated filled thermoplastic compounds. The performance of such compounds relative to crosslinked polyethylene PE has been compared in an earlier study.3 International Wire & Cable Symposium
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It is important to note that the Salt Fog test is a constant flow test that simulates conditions that are not likely to occur in nature. This test method is currently under review by the IEEE Fiber Optics Standards Committee.
Figure 2. Electrical setup. R
Hot
Accelerated Electrical Testing. To simulate more realistic in-service environmental conditions on high voltage networks, an experimental setup subjected the cables to a series of wet and dry cycles, an extreme example of preconditions for dry band arcing. An experimental set-up was built indoors in Arizona State University’s High Voltage Laboratory. This test setup is based on the theory of capacitive coupling and uses a Thevenin Equivalent circuit to model the electrical behavior of an ADSS cable installed near phase conductors.10 Figure 2 shows the high voltage electrical connections and Figure 3 shows the experimental set-up. Similar to the Salt Fog test, the water reservoir contains water and NaCl (salt) to simulate the effects of precipitation and pollution. Table 2 shows the electrical and pollution levels each cable was subjected to.
Variac
Water Spray
Thevenin Impedance
Return PT Xformers
gap HV Thevenin 47 Ohm
Measuring Point for DAQ
Figure 3. Test setup with electrodes. Measured Signals
High Voltage
Galvanized Tank
Series Impedance
47Ω
gap
Flow Meter
Three levels of resistance of the cable representing a given pollution level have been suggested in previous research on the dry band arcing phenomenon: 11 1. Light: 3.0 MΩ/m 2. Medium: 1.0 MΩ/m 3. Heavy: 0.1 MΩ/m
Pump Water solution reservoir DAQ CPU & Process control
-Cable Setup The cable samples tested had end plugs at both ends to prevent the interior of the fiber-optic cable from getting wet. The test cables were approximately 18 inches long. Two electrodes were attached to the fiber-optic cables, namely the high voltage and low voltage electrodes. The electrodes were spaced 2.5 in. 6.35 cm (± 0.5 cm) apart for all sets of experiments. The high voltage electrode was connected to the output side (high side) of the transformers and then to a series current limiting impedance and then to the cable’s sheath. The cables were placed inside a galvanized metallic tank.
Table 2: Accelerated Electrical Test Key Parameters. Pollution Level Open Circuit Voltage (kV) (MΩ/m) Cable A 12 0.1 Cable B 20 0.1 Cable C 30 0.1 Cable D 30 0.1
-High Voltage Electrical Setup The high voltage electrical setup is shown in Figure 2. High voltage is supplied through high voltage transformers. The high voltage is directly applied to the cables through a current limiting impedance.
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-Spray System To simulate the environmental conditions of rain with pollution, a salt-water solution is sprayed onto the cable under test. The pump periodically cycles 2.0 minutes on and 13.0 minutes off. The spray system consists of five lateral-spread nozzles. The apparatus is pictured in Figure 5. The figure shows the top view of three spray nozzles. Two other nozzles are on the other side (not shown) and are equally spaced in between the three shown in the figure. The figure shows the water solution being sprayed.
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surface impurities can significantly reduce the electrical resistance to current flow on the surface of the cable.
Figure 5. Saltwater Spray Pattern
lateral-spread spray nozzeles
Due to the inherent hydrophobic nature of polyethylene, the newly extruded ADSS jacket is not prone to collection of moisture on the cable jacket surface. As the cable surface begins degradation due to heat, UV-radiation, or exposure to ozone the cable sheath material may be wetted from rainfall. Additionally resistance may be lowered from salt or pollution. With a wetted and/or polluted cable surface, dry bands of high resistance surrounded by wetted sections of much lower resistance may develop. As these bands develop, the possibility exists for arcing across the dry band exists, which can damage an unprotected sheath by heat and ablation (vaporizing of jacket material causing pitting).
fiber optic cable
The spray nozzles were set up so that the region of electrical testing received the majority of the water. The flow rate of water was measured using an in-line flow meter. The water spray creates a wet conductive layer on the fiber optic cable sheath. The longitudinal field generated by the high voltage drives a current through this conductive layer. The current-limiting impedance limits the current. This current initiates the dry-band arcing process as the conductive layer dries.
The rate of aging and the subsequent changes of surface properties of the cable are highly dependent on the region in which the cable is installed. In regions where UV exposure is low and climates are moderate such as northern Europe, aging effects will be minimal. However, in regions such as southern China where average temperatures are high, UV-exposure is high, and pollution levels are high the risk of dry-band arcing will be greater.
Aging Effects To simulate the worst case scenario for dry band arcing, the cables were aged at 85oC temperature and at 85 % relative humidity for 30 days before electrical testing. Additionally, cables were aged in a UV weatherometer to examine how UV aging would effect the electrical behavior of materials.
Global maps of average temperatures, rainfall, and sunshine are shown in figures 5-7.13 Average UV dose was calculated and correlated to UV aging studies.14 Depending on climatalogical region, mean temperatures can vary by 20°C or more, rainfall can vary by a factor of 100 or more, and annual UV dose can vary by a factor of 3 or more. The combined effects cause large variation on the aging of the cable surface, and therefore, the resulting changes in cable surface properties as a function of time. Consequently, cable lifetime and optimal installation configuration cannot be accurately determined unless climatological factors are included as part of the installation and service guideline scenario.
Surface Contact Angle Measurement In order to determine the effects of aging on the hydrophobicity of the various jacket materials, a single drop of deionized water was carefully placed on the surface of each material. The shape of the drop and contact angle were then imaged with an optical microscopy system interfaced to a digital imaging system. Images of cleanvirgin samples of each material were compared to aged and aged, polluted samples. Contact angle measurements were made from these images.
Similarly, other factors such as pollution, ozone, dust, or aerosols can influence the surface properties of cables and/or accelerate material degradation. Pollution levels can vary highly from nation-to-nation and from locality to locality. Seasonal variation in winds and other factors such as wildfires can also have effects on overall atmospheric particulate matter, and cables installed in coastal regions can experience the added risk of salt-spray. In areas of known high-risk levels of surface contamination, guidelines should be conservative to account for the effects of surface pollution on the electrical properties of the outer jacket.
The adhesion tension between deionized water and the jacket material can be determined by multiplying the cosine of the contact angle by the surface energy of the air/water interface. The surface tension (energy) of the air/water interface is 72.5 dyn/cm at room temperature.12 AGING AND ENVIRONMENTAL EFFECTS Performance of cables in electrical fields is highly dependent on the aging of the cable. On a newly installed dry cable, the surface sheath resistance is obviously quite high (>109 Ohm/m) so the induced currents are insignificant. Additionally, the cable surface is highly hydrophobic so moisture and contaminants are not prone to build up and thereby reduce surface resistivity. However, as a cable ages from thermal oxidation and exposure to ultraviolet rays from the sun, contaminants such as salt, pollutants, and moisture adsorb on the cable sheath. The
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Comparisons of industrial emissions and particulate pollution deposition data reveals large variation in pollution levels from region to region.15,16,17,18 Total pollution levels and trends are highly variable and also dependent on seasonal weather patterns as well as natural events such as volcanic activity and wildfires. More specific details on trends and actual composition of surface pollution are
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available from the references cited herein. Due to differences in national regulation, maximum pollution levels between the U.S., Europe, and Asia can vary by a factor of 10. Additionally, regional variation can be even greater.
Table 3: Percentage change in tensile strength due to heat aging, UV aging, and heat followed by UV aging. % change in tensile strength Heat UV
RESULTS AND DISCUSSION
Cable A
Cable B
Cable C
Cable D
+2.6 -1.9
+8.7 +3.4
-24.9 -7.3
-15.5 -4.6
Effect of Aging on Mechanical Performance of the Heat+UV -8.0 -5.1 Outer Cable Jacket Change in Tensile strength and Elongation of the cable Table 4: Percentage change in elongation outer jacket materials after heat aging, UV aging, and heat due to heat aging, UV aging, and heat followed aging followed by UV aging are listed in Table 3 and Table by UV aging. 4. % change in ultimate elongation Table 3 and Table 4 illustrates that the heat aging and UV Cable A Cable B Cable C Cable D aging conditions used for this study did not produce significant changes in ultimate material properties relative Heat +6.0 +15.0 -26.0 +32.0 to the changes in surface properties. For jacket material D UV -12.9 +6.7 -33.0 +27.0 an annealing effect from aging appears to be increasing Heat+UV -37.5 +8.7 ultimate elongation. Jacket material C is the only material that shows measurable degradation in material properties after aging. Figure 5. Global Map of Average Temperatures.
Figure 6. Global Map of Average Rainfall.
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Figure 7. Global Map of Average Sunshine.
The total U.V. dose received during the 10 Day U.V. test was 220 KWh/m2 or (792 MJ/m2). This U.V. dose is equivalent to direct exposure in southern Arizona for about 1 year, direct exposure in Miami for about 1.5 years, or direct exposure in Northern Europe for about 3 years.11 The amount of damage accumulated during U.V. testing was compounded by the 50°C test temperature, which is almost 30°C hotter than the average temperature for southern Arizona and 40°C hotter than for northern Europe. Black surfaces, however, can easily reach this temperature in the southern U.S.
Effect of Aging and Pollution on Surface Properties Figure 8 and Tables 5 & 6 summarize the results of contact angle measurements between deionized water droplets and jacket surfaces. From the figure it is obvious that both pollution and aging have a significant influence on the contact angle. The adhesion tension (ASLV) between deionized water and the jacket material can be determined by the following equation: ASLV= γLV * Cos θ = 72.5dyn/cm * Cos θ.
(1)
Where γLV ,72.5 dyn/cm, is the surface tension (energy) of the air/water interface at room temperature.19 If the adhesion tension between water and the jacket material increases above 72.5 dyn/cm, wetting of the cable surface will occur.
In comparison to heat aging, where physical changes occur more uniformly throughout the material, UV aging localizes most of the damage to the surface of the material. The effects of UV on the surface properties are far more significant than the effects of either heat or UV on the bulk properties of the jacket material. Since the surface properties of the material are far more important for determining the overall electrical properties of the cable, surface measurements are far more useful in determining material robustness relative to real-world weathering effects.
After UV aging the adhesion tension increased substantially for all materials studied. The filled thermoplastic materials showed better UV damage resistance than the unfilled materials. The effects of UV aging on surface properties were far more significant than the effects of UV or heat aging on bulk mechanical properties. Relative changes in adhesion tension were up to several hundred percent, although, no significant aging effects were noted from tensile testing. These results indicate that, especially for UV aging, material damage is concentrated on the cable surface, where it is most likely to alter electrical properties.
Table 5: Adhesion Tension Measurement Results. Adhesion Tension (dyne/cm)
Although there was substantial variation in the adhesion tension of the virgin materials, all of the polluted surfaces had nearly identical adhesion tension. This phenomenon indicates that once a certain level of cable pollution is present, pollutant type and concentration dominate the surface electrical properties. Pollution increased the adhesion tension by 12 to 28 dyne/cm and was equal in significance to UV effects. International Wire & Cable Symposium
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Cable A
Cable B
Cable C
Cable D
Virgin
6.3
13.8
19.4
2.5
Heat Aged
12.6
20.7
25.9
9.5
UV aged
42.6
29.5
29.5
30.0
Polluted
29.5
31.8
31.8
30.6
Aged and Polluted
41.6
45.6
45.6
30.6
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A, a with a standard HDPE outer jacket fails in short order under the harsh conditions and 30 kV.
Table 6: Change in Adhesion Tension Due to UV Aging and Pollution. Change in Adhesion Tension Heat aging UV aging Pollution Heat aging + pollution
Cable A
Cable B
Cable C
Cable D
6.3 36.3 23.2 35.3
6.9 15.7 18.0
6.5 10.1 12.4
7.0 27.5 28.1
31.8
26.2
28.1
Table 7: IEEE P1222 Draft 1997 Annex A Salt Fog Test Results. Cable A Cable B Cable C Cable D Virgin Heat Aging
Results of Salt Fog Testing Table 7 summarizes the results of the salt fog testing carried out in accordance with IEEE P1222 Draft 1997 Annex A. This is a pass/fail test method where very little can be drawn from the results, other than the fact that Cable
Fail (1.6 h) N/A
Pass
Pass
N/A
Pass
Pass
N/A
Results of Accelerated Electrical Testing The accelerated electrical testing resulted in a ranking of the four cables that were tested. Cable B performed the best followed by Cables C, D and A respectfully.
Figure 8: Contact Angle Measurements of Virgin, Aged, and Polluted Cable Samples.
b b
b
θ
θ
a
a
Cable A - Virgin θ = 85° ASLV = 6.3 dyne/cm
a
Cable A – UV aged. θ = 54° ASLV = 42.6 dyne/cm
Cable A – Aged and polluted θ = 55° ASLV = 41.6 dyne/cm
b
b
b θ
θ
θ
a
a
Cable B - Virgin θ = 79° ASLV = 13.8 dyne/cm
a
Cable B – UV aged. θ = 66° ASLV = 29.5 dyne/cm
Cable B – Aged and polluted θ = 51° ASLV = 45.6 dyne/cm
b b
b
θ
θ
a
a
Cable C – Virgin. θ = 75° ASLV = 19.4 dyne/cm
a
Cable C – UV aged. θ = 66° ASLV = 29.5 dyne/cm
Cable C – Aged and polluted θ = 51° ASLV = 45.6 dyne/cm
b
b b
θ a
Cable D – Virgin θ = 88° ASLV = 2.5 dyne/cm
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a Cable D – UV aged. θ = 65° ASLV = 30.6 dyne/cm
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Cable D – Aged and polluted. θ =65° ASLV = 30.6 dyne/cm
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kV, a threshold value used by some cable manufacturers for their standard jacket material.
Figures 9, 10, and 11 are representative plots of IMSQ vs. Time of a wet and dry cycle from the accelerated electrical testing performed at the ASU Electrical Engineering Department laboratory. Figure 9 shows current on a virgin cable rising dramatically then stabilizing at a constant value that indicates the cable is fully saturated with water. The current then remains level afterward for a short period after the spray is turned off, then becomes somewhat erratic for a short period indicating dry band arcing activity. However, the current then quickly falls off indicating a cessation of the arcing. This is a key indication that the virgin cables indeed show a high level of hydrophobicity.
Cable A - UV Aged + Temp/Humidity Aged 1.00E-05 Wet Cycle
Dry Cycle
IMSQ (A^2)
8.00E-06 6.00E-06 4.00E-06 2.00E-06 0.00E+00
Cable B - Virgin 2.00E-05
Wet Cycle
-
Dry Cycle
50.00
100.00 150.00 200.00 250.00 300.00 Time
Figure 11: IMSQ plot of Cable A – Virgin. IMSQ (A^2)
1.50E-05
CONCLUSIONS Aging and pollution effects have been shown to significantly alter surface properties of ADSS cable jacket materials representative of a variety of materials used throughout the industry. These changes in surface properties have been correlated to significant differences in electrical test results simulating dry-band arcing. Based on a combination of surface property measurements and electrical test results on a variety of aged and unaged cable materials in this and previous studies, it is recommended that jacket material selection and installation guidelines be determined by electrical test data from aged cable samples. Installation guidelines using test data from aged cable samples will be more accurate for normal service life regardless of the type of jacketing material used. The use of aged cable data will ensure cable system robustness even if a combination of environmental and electrical factors act in combination. Guidelines for installation made without taking aging and pollution effects into account will not accurately assess the risk of system failure. Finally regional climatological factors should be an integral part of deciding where to place ADSS in the high voltage power system.
1.00E-05
5.00E-06
0.00E+00 -
50.00
100.00 150.00 200.00 250.00 300.00 Time
Figure 9: IMSQ vs. Time plot of Cable B – Virgin In contrast, Figure 10 shows that in an aged cable, the current rises dramatically and somewhat sooner than the virgin cable, but then becomes erratic and never levels or drops off indicating a prolonged arcing period. This yields the conclusion that UV and Temperature / Humidity aging facilitates a more hydrophilic surface in which dry band arcing occurs sooner and lasts longer. Cable B - UV Aged + Temp/Humidity Aged 2.00E-05
Wet Cycle
Dry Cycle
IMSQ (A^2)
1.50E-05
1.00E-05
ACKNOWLEDGEMENTS We would like to thank Alstom UK Ltd. For their contribution on the salt-fog testing. We would also like to thank Monty Tuominen of Bonneville Power Administration for his assistance in understanding the accelerated electrical test results.
5.00E-06
0.00E+00 -
50.00
100.00 150.00 200.00 250.00 300.00 Time
Figure 10: IMSQ plot of Cable B – UV Aged and Temp/Humidity Aged.
REFERENCES 1
Besztercey, G., Karady, G., and Tuominen, M. W. “Corona Caused Deterieration of ADSS Fiber-optic Cables on High Voltage Lines.” IEEE Transactions on Power Delivery, 14, No. 4 October 1999, 1438-47.
Figure 11 shows the complete IMSQ vs. Time plot for the virgin sample of Cable A. As indicated by the erratic behavior in the wet cycle, arcing began almost immediately and continued until this sample failed prior to completing the first wet/dry cycle. It is important to recall that this sample was tested at an equivalent space potential of 12
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Karady, G., et. al. “A Mitigation Method for Dry-band Arcing Caused Deterioration of ADSS Fiber-optic Cables”,
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Proceedings of The IEEE Power Engineering Society Winter Meeting, 4, 2000, 2391-6.
RAINS – Asia, International Institute for Applied Systems Analysis, Laxenburg, Austria.
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19
Tuominen, M.W., Bonneville Power Administration, private communications
Kaser, V., J. Colloid and Surface Sci., 56, 622 1972.; Adamson, A.W. Physical Chemistry of Surfaces, Wiley, New York, 1990.
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Keller, D.A, D.J. Benzel, J.P. Bonicel, C. Bastide, F. Davidson, “Continued Investigation of ADSS Designs and Reliability Considerations with respect to Field Voltage Tracking and Cable Installation Practices”, Proceedings of the 46th International Wire and Cable Symposium, November 1997.
AUTHORS Swati NEOGI
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Vaughan, A.S., S.G. Swingler, M. Lanfear, H. Weingandt, and H. White, “Laser Ablation and Thermal Decomposition Studies of Fiber Optic Cable Sheathing Materials”, IEEE proceedings, October 1992, 501-510.
OFCCC Alcatel Telecommunications Cable
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Vaughn A.S., Robbie D A., Hosier I.L., Sutton S.J., “Simulations of Surface Discharge Damage on Self Supporting Fiber Optic Cables”, Plastics in Telecomm Proceedings, 6E, September 1998, 87-96.
2512 Penny Rd. P.O. Box 39 Claremont, NC 28610
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Carter, C., et al., “Mathematical Model of Dry Band Arcing on Self Supporting All Dielectric Optical Cables on Overhead Power lines”, IEE Proceedings-C, 139, No 3, May 1992, 18596.
Swati Neogi is a Senior Material Scientist and Project Manager at Alcatel’s Optical Fiber Cable Competence Center. She received her Ph.D in Chemical Engineering from Ohio University. During her doctorate studies, she worked on modeling of simultaneous mass transfer and reaction of disc ring reactor used in the manufacturing process of polyethylene terepthalate. Before joining Alcatel in 1996, she worked in commissioning a PET plant.
8
Rowland S., et al. “Electrical Aging and Testing of Dielectric Self Supporting Cables for Overhead Power lines”, IEE Proceedings-A, 140, No 5, September 1993, 351-56.
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Neogi, S, Risch, B.G., and Soltis, M., “Materials Reliability of Flooded and Dry-Core ADSS Cable”, Proceedings of the 48th International Wire and Cable Symposium, November 1999, 795806.
Brian G. RISCH
10
R.G. Olsen, “An improved model for the electromagnetic compatibility of all-dielectric self-supporting fiber optic cable and high voltage poser lines,” IEEE Transactions on Electromagnetic Compatibility, 41, No 3, August 1999.
OFCCC Alcatel Telecommunications Cable
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G.G. Karady, S. Devarajan, M. Tuominen, “Novel technique to predict dry band arcing failure of fiber optic cables installed on high voltage lines,” IEEE Power Tech ’99 Conference, AugSept 1999, Paper PBT99-160-30, Budapest, Hungary.
2512 Penny Rd. P.O. Box 39 Claremont, NC 28610
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Kaser, V., J. Colloid and Surface Sci., 56, 622 1972.; Adamson, A.W. Physical Chemistry of Surfaces, Wiley, New York, 1990.
Brian G. Risch is the Materials Technology Manager at Alcatel Telecommunications Optical Fiber Cable Competence Center. He holds a B.A. degree in Physics from Carleton College and a Ph.D. in Materials Science and Engineering from Virginia Polytechnic Institute and State University. His Ph.D. research was in the area of polymer crystallization and structural property relationships in polymers. Directly after he finished his Ph.D. he worked for ORD laboratories in the area of optical polymers developing new polyurethane and polythiourethanes for high performance ophthalmic lens applications. Since 1996 Brian has worked for Alcatel’s Optical Fiber Cable Competence Center (OFCCC) in the area of thermoplastic cable materials. His specialization has been in the area of and crystallization behavior and materials reliability for thermoplastic cable materials.
13
Data compiled by FAO-Environmental and Natural Resources Service (SRDN) Agrometerology Group, 1997. 14 De Jong, B., Net Radiation Received by a Horizontal Surface at the Earth, Delft University Press, 1973. 15
International Institute for Applied Systems Analysis, Laxenburg, Austria. Data complied from CORINAIR ‘90/94 and EMP/CLRTAP emission data. 16
1998 National Air Quality and Emission Trends Report, EPA Office of Air Quality Planning and Standards. Research Triangle Park, NC, March 2000. 17
Clean Air Status and Trends Network (CASTNet) 1998 Annual Report, U.S. Environmental Protection Agency Office of Air Quality Planning and Standards, Research Triangle Park, NC, August 1999.
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William F. DeWITT OFCCC Alcatel Telecommunication Cable
George G. KARADY Arizona State University
2512 Penny Rd. P.O. Box 39 Claremont, NC 28610
Tempe, AZ 85287
William F. DeWitt is a Development Project Manager at Alcatel Telecommunications Optical Fiber Cable Competence Center. He holds a B.S. in Mechanical Engineering from Grove City College and a Masters in Business Administration from The Pennsylvania State University. Prior to joining Alcatel in 1999, William worked for AMP, Incorporated in a variety of positions ranging from Manufacturing Engineer to Plant Manager.
George G. Karady received his BSEE and Doctor of Engineering Degrees in electrical engineering from Technical University of Budapest in 1952 and 1960 respectively. Dr. Karady was appointed to Salt River Chair Professor at Arizona State University in 1986. Previously he was with EBASCO Services where he served as a Chief Consulting Electrical Engineer, Manager of Electrical Systems, and Chief Engineer of Computer Technology. He was Electrical Task Supervisor for the Tokomak Fusion Test reactor project in Princeton. Dr Karady is a registered Professional Engineer in New York, New Jersey, and Quebec. He is the author of more than 100 technical papers.
Pierre COAT OFCCC Alcatel Telecommunications Cable 2512 Penny Rd. P.O. Box 39 Claremont, NC 28610
Johnny A. MADRID
Pierre Coat joined Alcatel in 1992 after receiving his degree in Photonic and Optical Sciences in Lannion, France and completing a 2 months study program on optical fiber characterization at France Telecom. He is currently a microscopist and spectroscopist in the Material Development Laboratory at Alcatel Telecommunication Optical Fiber Cable Competence Center.
Arizona State University Tempe, AZ 85287 Johnny Madrid received his BS degree in Electrical Engineering from New Mexico State University in 1994 and a MS degree in EE from Arizona State in 2000. During his MS he worked on experimental test for correlating dry band arcing damage on ADSS cables to time to failure. Prior to attending school, Johnny worked for the Los Alamos National Laboratory on the Lunar Prospector Mission, part of NASA’s discovery program, from 1996 to 1998. He also served in the United States Army during Desert Shield and Desert Storm in 1991.
James D. AMMONS OFCCC Alcatel Telecommunication 2512 Penny Rd. P.O. Box 39 Claremont, NC 28610 James D. Ammons is a microscopist and material analyst at Alcatel Telecommunication Optical Fiber Cable Competence Center. He received his B.S. in Physics/ Mathematics from Lenoir-Rhyne College in Hickory, North Carolina. Before joining Alcatel, he served 5 years in the United States Navy and the U.S. Marine Corps.
International Wire & Cable Symposium
346
Proceedings of the 49th
