DOCSLIB.ORG

Delft University of Technology a Review on Stray Current-Induced

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Delft University of Technology a Review on Stray Current-Induced Delft University of Technology A review on stray current-induced steel corrosion in infrastructure Chen, Zhipei; Koleva, Dessi; van Breugel, Klaas DOI 10.1515/corrrev-2017-0009 Publication date 2017 Document Version Final published version Published in Corrosion Reviews Citation (APA) Chen, Z., Koleva, D., & van Breugel, K. (2017). A review on stray current-induced steel corrosion in infrastructure. Corrosion Reviews, 35(6), 397-423. https://doi.org/10.1515/corrrev-2017-0009 Important note To cite this publication, please use the final published version (if applicable). Please check the document version above. Copyright Other than for strictly personal use, it is not permitted to download, forward or distribute the text or part of it, without the consent of the author(s) and/or copyright holder(s), unless the work is under an open content license such as Creative Commons. Takedown policy Please contact us and provide details if you believe this document breaches copyrights. We will remove access to the work immediately and investigate your claim. This work is downloaded from Delft University of Technology. For technical reasons the number of authors shown on this cover page is limited to a maximum of 10. Corros Rev 2017; 35(6): 397–423 Zhipei Chen*, Dessi Koleva and Klaas van Breugel A review on stray current-induced steel corrosion in infrastructure https://doi.org/10.1515/corrrev-2017-0009 Received January 23, 2017; accepted September 29, 2017; 1 Introduction previously published online November 9, 2017 1.1 Corrosion of steel in infrastructure Abstract: Metallic corrosion can cause substantial damage at various levels and in almost all types of infrastructure. Corrosion, from the Latin “corrodere”, means “to chew For metallic corrosion to occur, a certain external environ- away” or “to attack” a material as a result of chemical ment and the presence of corrodents are the prerequisites. and/or physical interaction between this material and its Stray current-induced corrosion, however, is a rather environment. Corrosion is not limited to metals only but underestimated issue in the field of corrosion and civil affects other materials as well (glass, wood, polymers, engineering. Stray current arising from power sources and ceramics, etc.), which also corrode or degrade during their then circulating in metal structures may initiate corrosion service life (Landolt, 2007). The subject of this paper is the or even accelerate existing corrosion processes. The most corrosion of metals, particularly steel, which is a main frequent sources of stray current are light rail transits and construction material for infrastructure worldwide. Addi- subways, which are also main traffic tools with continu- tionally, from more than 60 categorized corrosion types, ously accelerating urbanization all over the world. Stray as recognized in the field of corrosion science and engi- currents from these systems may easily flow into nearby neering (Vandelinder, 1984), the topic of this work is elec- metallic structures, making stray current-induced corro- trochemical corrosion, specifically stray current-induced sion the most severe form of damage of buried structures, steel corrosion. such as tunnels, pipelines, and various underground rein- Most metals and alloys, when in contact with their forced concrete structures. The objective of this paper is to surrounding medium such as atmosphere or water, tend critically review stray current-induced steel corrosion in to convert to a more thermodynamically stable state by infrastructure with regard to sources of stray current and forming oxides/hydroxides on their surface. This process the characteristics and mechanism of stray current corro- follows chemical and electrochemical reactions with the sion in view of electrochemical aspects. The methods and external environment. In the long term, these interactions techniques for the evaluation, monitoring, and control of or the corrosion process itself would lead to the degra- stray current-induced corrosion for steel and reinforced dation of metals and to the reduction of their functional concrete structures are also presented and discussed. properties. Keywords: electrochemical aspects; steel in infrastruc- Steel corrosion can be and often is the primary cause ture; stray current corrosion. of damage to various types of infrastructure, such as steel bridges, reinforced concrete structures, pipelines, and marine platforms. It is estimated that corrosion destroys one quarter of the world’s annual steel production, which corresponds to about 150 million tons/year or 5 tons/sec (Landolt, 2007). A study in the United States calculated the direct cost of corrosion to be $276 billion, which cor- responds to 3.1% of the U.S. gross domestic product (GDP) *Corresponding author: Zhipei Chen, Department of Materials in 2002 (Koch et al., 2002). and Environment, Faculty of Civil Engineering and Geosciences, Corrosion damage is not always visible to the public Delft University of Technology, Stevinweg 1, 2628 CN, Delft, but nevertheless can lead to structural failure, loss of life, The Netherlands, e-mail: [email protected]; loss of capital investment and environmental damage [email protected]. http://orcid.org/0000-0002-7670-4050 (Koch et al., 2002). Therefore, as more and more aging Dessi Koleva and Klaas van Breugel: Department of Materials and Environment, Faculty of Civil Engineering and Geosciences, infrastructure reaches the end of its designed lifetime, the Delft University of Technology, Stevinweg 1, 2628 CN, Delft, The emphasis in the field of civil engineering today is on main- Netherlands taining and extending the service life of valuable assets. Brought to you by | Bibliotheek TU Delft Authenticated Download Date | 12/11/17 2:40 PM 398 Z. Chen et al.: Stray current-induced corrosion To fulfill this, the control of steel corrosion must be con- destroyed and the uniform corrosion of the steel reinforce- sidered and implemented. ment is at hand. Due to low cost and ease of forming at ambient tem- Chloride ions penetrate into the concrete cover by dif- peratures, reinforced concrete is the most widely used fusing through the pores or through cracks. When chlo- construction material and forms an important part of ride ions reach the surface of the rebar and accumulate infrastructure worldwide. The synergy of both materials to a certain critical value (chloride threshold concentra- (i.e. concrete and steel) provides a combination of high tion), they damage the passive film and localized corro- compressive strength and high tensile properties. There- sion (pitting corrosion) will be induced (Jang & Oh, 2010). fore, reinforced concrete is a composite material of global Irrespective of the factor responsible for corrosion initia- use and serves a variety of applications. Although rein- tion, once the passive film is destroyed, the surface of the forced concrete is considered to be of high durability, it corroding steel will function as a mixed electrode that can suffer from various degradation mechanisms related is a “composite” of anodes (active areas) and cathodes to either concrete or steel. (nonactive areas). The separation of anodic and cathodic The corrosion of steel reinforcement has been iden- areas on the steel surface results in a potential difference tified as the main reason for reduced service life of rein- and triggers oxidation and reduction reactions. During forced concrete structures. With proper construction work the corrosion process, electrons flow from the anodic to and adequate maintenance of a civil structure, steel corro- the cathodic areas, whereas ions flow in the surrounding sion would be theoretically minimum during the overall electrolyte (i.e. a corrosion cell forms). The concrete pore designed service life. However, the penetration of aggres- water functions as the aqueous medium (i.e. it serves as sive substances as well as the combination of environmen- a complex electrolyte). As the corrosion process becomes tal factors and exploitation conditions result in premature stable, the anodic oxidation and cathodic reduction reac- degradation of reinforced concrete structures due to steel tions will reach equilibrium (i.e. the potential of steel corrosion. The results are structural failure and enhanced reaches equilibrium at the corrosion potential, Ecorr), at health and safety risks. which point the net exchange current is zero. The corro- Steel reinforcement in reinforced concrete is normally sion cell that forms on a rebar surface is shown in Figure 1. in a thermodynamically stable state. Steel passivity is due The anodic reaction, or the oxidation process, results to the high alkalinity of the concrete matrix and concrete in the dissolution or loss of metal, whereas the cathodic pore water, respectively (pH of 12.5–12.9). Additionally, reaction for reinforced concrete is mainly the reduction of concrete acts as a physical barrier: well-consolidated dissolved oxygen, forming hydroxyl ions. For steel embed- and properly cured concrete with an optimum water-to- ded in concrete, the following are the most probable cement (w/c) ratio has a low permeability and acts as a anodic reactions (Ahmad, 2003): barrier against the penetration of corrosion-inducing 2+− Fe →+Fe 2e (1) substances, such as chloride ions or carbon dioxide (CO ; Ahmad, 2003). The high electrical resistivity of the 2 2Fe3+→HO Fe O+6H+−+6e concrete matrix, through blocked or disconnected pore 223 (2) pathways, impedes the steel corrosion rate by simply Fe +→2H OHFeO+−+3H
Load more

Recommended publications
  • Stray Voltage Problems with Dairy Cows
    AGRICULTURAL EXTENSION SERVICE Extension Folder 552-1980 UNIVERSITY OF MINNESOTA STRAY VOLTAGE PROBLEMS <- WITH DAIRY COWS R. D. Appleman and H. A. Cloud Many dairymen are losing milk pro­ dairymen. The number of cows Even when the stray voltage duction and experiencing cow affected and the severity of the problem has been corrected, milk health problems at milking time due milk let-down problem appear to production may remain abnor­ to small currents of electricity pass­ be dependent on the level of mally low for awhile because of ing through the cows' bodies. This stray voltage present. The mech­ the associated problems. condition may be caused by low anism of how this occurs is not It must be remembered that voltages existing on the grounded understood. When milk out is other factors such as mistreatment, neutrals of the farm electrical sys­ uneven, more machine stripping milking machine problems, disease, tem. Stray voltages can result from is required and longer milking sanitation, and nutritional disorders several electrical sources, but the time becomes apparent. can create problems which manifest major problem appears to be volt­ 2. Cows extremely nervous while in themselves in the above seven ages existing on the grounded neu­ the parlor. This trait often is char­ symptoms. A careful analysis of all tral network. acterized by the cows dancing or possible causes is necessary if the The prevalence of this problem stepping around almost continu­ proper corrective procedure is to be in Minnesota remains uncertain, but ously while in the parlor stall. found. the authors have been directly in­ However, dairymen are re­ volved on more than 50 farms in a 2- minded that cows may become WHAT CAUSES STRAY year period.
    [Show full text]
  • Electric Distribution Grounding & Stray
    ONLINE COURSE ELECTRIC DISTRIBUTION GROUNDING & STRAY VOLTAGE March 25-26, 2020 Online | Central Time “EUCI organized and coordinated a training class that was well put together and focused on attendees and content.” Electric Utility Engineer III, City of Tallahassee EUCI ONLINE COURSE In lieu of recent developments with COVID-19 we have, for the health and safety of our speakers and attendees, decided to move many of our events to Online Courses. This will enable you to view the courses from the comfort of your location while still benefitting from the depth of knowledge provided at our courses. The option is available on the registration page of all of our courses and hope you will be able to take advantage! TAG US #EUCI FOLLOW US @EUCIEvents EUCI is authorized by IACET to offer 1.1 CEUs for the course ELECTRIC DISTRIBUTION GROUNDING & STRAY VOLTAGE March 25-26, 2020 | Online OVERVIEW The electric distribution ground system is a complex network of various paths and accommodates the return current back to the substation. Ohm’s Law tells us that any current passing through an impedance creates a voltage. If we acknowledge that the ground path(s) is not a perfect conductor, we know that stray voltage is inevitable. This course provides insight into the workings of the grounding system from the end user back to the substation. Attendees learn the causes of high ground currents, how they can be minimized, and the techniques to mitigating stray voltage. LEARNING OUTCOMES • Review the basic electrical formulas associated with grounding and
    [Show full text]
  • IOWA STRAY VOLTAGE GUIDE a Guide Addressing Stray Voltage Concerns JULY 2014 JULY
    IOWA STRAY VOLTAGE GUIDE A Guide Addressing Stray Voltage Concerns JULY 2014 JULY This document supplements the United States Department of Agriculture Hand- book 696 titled “Effects of Electrical Voltage/Current on Farm Animals: How to Detect and Remedy Problems” December 1991, commonly referred to as the Red Book. The following organizations developed this guide. Iowa Association of Electric Cooperatives PREFACE Sponsoring Organizations : Alliant Energy Unless stated otherwise, permission is granted to reproduce these materials if the content is Iowa Association of Electric Cooperatives Iowa Association of Electric Cooperatives not altered. Reproduction via copy machine or other copy technology is permissible. Also, the Iowa Cattlemen’s Association material can be reproduced in newsletters and other distribution methods. If the materials are reproduced in a newsletter, magazine, web site Iowa Energy Center or other method of distribution, please notify the Iowa Association of Electric Cooperatives at 515.276.5350. This notification is for informational Iowa Farm Bureau Federation purposes to track the usage of our materials. Iowa Institute of Cooperatives Disclaimer Iowa State Dairy Association The information in this guide is intended for use as educational material to assist utility representatives, farmers and their advisors to understand processes and procedures that can be used to resolve stray voltage concerns. Identification and diagnosis of stray voltage problems can sometimes be difficult and requires electrical expertise. Working with electrical systems can be dangerous. Voltages that cause stray voltage problems are normally so low they cannot be detected without special instruments. A possible hazard to life exists if an electrical shock can actually be felt or if animals are knocked down.
    [Show full text]
  • Iffects of Electrical Voltage/Current on Farm Animals
    ?0i^ UnHed States ^ Department of Agriculture iffects of Electrical Agricultural Research Service Voltage/Current Agriculture Handbook Number 696 on Farm Animals How To Detect and Remedy Problems a: - ; O; Lefcourt, A.M., ed. 1991. Effects of Electrical Voltage/Current on Farm Animals: How To Detect and Remedy Problems. U.S. Department of Agriculture, Agriculture Hand- book No. 696, 142 pp. This handbook examines 1) the history of stray voltage/current problems on farms, 2) the physical and electrical sources of stray voltage/current phenomena, 3) the physiological and behavioral bases for losses in milk production, 4) methods for iden- tifying and detecting stray voltage/current problems, 5) methods for mitigating such problems, and 6) areas where further research may be warranted. While the primary emphasis is on cattle and dairy farms, the theories and procedures discussed are com- pletely relevant to all tj^es of livestock and livestock housing facilities. Recommenda- tions are made for action levels and concerning mitigation techniques. The fundamental conclusion of this handbook is that stray voltages/currents can be reduced to acceptable levels. KEYWORDS: Stray voltage/current, neutral-to-earth voltage, electrical shock, history, sources, physiological effects, behavioral modifications, mitigation, dairy farms, cows. Trade names are used in this publication solely to provide specific information. Men- tion of a trade name does not constitute a guarantee or warranty of the product by the U.S. Department of Agriculture or an endorsement by the Department over products not mentioned. Copies of this publication can be purcliased from the Superintendent of Documents, Govern- ment Printing Office, Washington, DC 20402.
    [Show full text]
  • Impact of Transmission Lines on Stray Voltage
    1 Impact of Transmission Lines on Stray Voltage Nagy Abed, Member, IEEE, Sasan Salem, Member, IEEE, and Jim Burke, Fellow, IEEE to simulate and measure the stray voltage. Figure 1 shows the Abstract-- The purpose of this paper is to study the effect of schematic diagram of the 115 kV transmission system used for transmission system parameters and operating conditions on the stray voltage study. This system was modeled using stray voltage levels. This includes the transmission line conductor EMTP-RV to evaluate the stray voltage level and the impact configurations, line loading levels, grounding system parameters, of various system parameters on these generated voltages. and unbalance loading. Excessive stray voltages levels may have a negative effect on dairy farm cows and endanger personnel safety. EMTP-RV was used to model the coupled electromagnetic- power circuit system. EMTP models of the poles and wires were built to represent the transmission line electromagnetic behavior and the stray voltage generation mechanism. The parameters of the proposed models were obtained from the technical literature. Different simulations were conducted by varying the system parameters and operating conditions. Calculations and field tests, which included the effect of earth contact resistance, indicated that most measured values of stray voltage may be incorrect and that the safety hazard to humans and animals may be greatly exaggerated. A discussion of these results is presented. Fig. 1 Schematic Diagram of the Modeled 115 KV Transmission Line System The transmission line model utilized in the study is a Index Terms—Stray Voltage, Induction, Transmission Line, Earth, Earth Current, Ground, Step Potential, Touch Potential distributed Constant Parameter (CP) model.
    [Show full text]
  • Appendix A: Summary of Public Comments
    Appendix A: Summary of Public Comments SE Twin Cities–Rochester–La Crosse Transmission System Improvement Project Macro-Corridor Study THIS PAGE INTENTIONALLY LEFT BLANK. SE Twin Cities–Rochester–La Crosse Transmission System Improvement Project Macro-Corridor Study Appendix A-1: MN CON Public Information Meetings (September 2007) SE Twin Cities–Rochester–La Crosse Transmission System Improvement Project Macro-Corridor Study THIS PAGE INTENTIONALLY LEFT BLANK. SE Twin Cities–Rochester–La Crosse Transmission System Improvement Project Macro-Corridor Study Comments Received The CapX2020 utilities received comments by several different means. Commenters could submit comments by forms, letters, email, fax, phone, or the project website by the deadline of October 31, 2007. Project representatives received comments at the public informational meetings on pre-printed comment forms and as written suggestions on sheet maps. The written comments on sheet maps were primarily site-specific information or concerns regarding the notice corridors. Project representatives also recorded comments and information requests with the approval or on request by attendees wishing to comment. After the public informational meetings, representatives responded to information requests. Approximately 80 comment forms and letters were received by project representatives either at the public informational meetings, by mail, phone call, email, or on the project website. Comment forms that were submitted by the deadline of October 31, 2007, were considered within this meeting summary. The most frequently identified issues on the comment form checklist were proximity to residences and land use, including agricultural, residential, and recreation land uses as indicated in Table 1. Other additional issues not listed in the table included decreased land and or property value, other land uses, cost and use of existing transmission line corridors, and providing more reliable power beyond the current study area.
    [Show full text]
  • Stray Voltage Testing Made Easy with U1272A
    Keysight Technologies Stray Voltage Testing Made Easy With U1272A Application Note Introduction Stray voltage, sometimes referred to as ghost voltage, is a voltage that appears in an electrical con- ductor such as a wire, even though the wire is disconnected from an electrical circuit. Electricians and technicians frequently encounter stray voltages in electrical systems when measuring the AC voltage in electrical circuits that have been disconnected. Measuring the circuit us- ing a high-impedance handheld digital multimeter can make it difficult to differentiate stray voltages from legitimate readings. In this situation, identifying and resolving the source of the stray voltage can cost time, effort, and money. This application note presents an alternative tool for identifying the presence of stray voltages: the Keysight Technologies, Inc. U1272A handheld digital multimeter (HH DMM.) This paper also explains how the U1272A’s ZLow feature makes it easy for technicians and electricians of every skill level to identify the presence of stray voltage in all types of electrical installations. To illustrate the differences in voltage measurement tools, this application note uses an actual situation in which stray voltage was identified. Finding Stray Voltage As Figure 1 illustrates, an electrician is installing low voltage lighting in a warehouse office. The warehouse is equipped with two wires running in parallel to the conduit. One is for light A, which is ON, and the other pair of wires will be used by the electrician to install a new light using a new expansion cable that is running parallel with light A. Before beginning the installation, he checks the voltage on the wire using his high-impedance handheld multimeter (shown in blue in the illustration.) He obtains a reading of 40 V, even though the line is disconnected from the main switch.
    [Show full text]
  • Electric Distribution Grounding & Stray Voltage
    ONLINE COURSE ELECTRIC DISTRIBUTION GROUNDING & STRAY VOLTAGE September 24-25, 2020 Online | Central Time “EUCI organized and coordinated a training class that was well put together and focused on attendees and content.” Electric Utility Engineer III, City of Tallahassee EUCI ONLINE COURSE EUCI is pleased to offer this virtual course on its online interactive platform. Enjoy a valuable learning experience with a smaller impact on your time and budget. You will gain new knowledge, skills, and hands-on experience from the convenience of your remote location. TAG US #EUCI FOLLOW US @EUCIEvents EUCI is authorized by IACET to offer 1.0 CEUs for the course ELECTRIC DISTRIBUTION GROUNDING & STRAY VOLTAGE September 24-25, 2020 | Online OVERVIEW The electric distribution ground system is a complex network of various paths and accommodates the return current back to the substation. Ohm’s Law tells us that any current passing through an impedance creates a voltage. If we acknowledge that the ground path(s) is not a perfect a conductor, we know that stray voltage is inevitable. This course provides insight into the workings of the grounding system from the end user back to the substation. Attendees learn the causes of high ground currents, how they can be minimized, and the techniques to mitigating stray voltage. LEARNING OUTCOMES • Identify the basic electrical formulas associated with grounding and stray voltage • Review how transient events create hazards which may be dangerous to the public and utility personnel, as well as damage equipment •
    [Show full text]
  • AC Mitigation - Part No
    AC Mitigation - Part No. 2 What can be done to avoid stray currents? Methods & Equipment __________________________________________________________________________________ Electricity plays a vital part in our daily life. To Imagine life without it is unthinkable today. In certain cases, electric current can stray away from its intended path and can flow in unintended circuits and materials. This flow of stray current causes the electrochemical deterioration of metallic surfaces, which is known as stray current corrosion. The magnitude of the deterioration is directly related to the extent of unintended current flowing in the structure. Localized faults in insulation and connections can result in localized stray currents causing localized corrosion damage. Structures in the surrounding area of high-voltage equipment and conductors attract stray voltages, even during normal fault-free operation of a high-voltage circuit. Some of the commonly occurring sources of stray currents are: • Grounded direct current (DC) power systems distributing and transmitting power to consumers • Electrically operated rapid transit systems • Corrosion protection systems designed with cathodic protection (CP) • Electrical welding equipment The minimization of the stray currents and voltages involves: • Detecting and measuring stray current as well as the source of the voltage and its path • Mitigation of defects and insulation failures • Repairing defective connections Why does stray current occur? Stray current occurs because of induced or leaked voltage, which is the unintended presence of a voltage difference between two objects, this is increasingly common as infrastructure of differing nature share servitude and right of ways. Ideally, these should have zero voltage difference between them. Even grounded objects at differing locations may have a voltage difference existing between them, and stray current may flow between them as a result.
    [Show full text]
  • Wind Turbines and Farm Stray Voltage
    February, 2014 Wind Turbines & Farm Stray Voltage Do wind turbines affect levels of stray voltage? Wind turbines generate electrical power in the same way as all other generation technologies. The only difference is in the source of the mechanical power supplied to the electrical gen- erator: wind, rather than a diesel engine or steam turbine, provides the energy. Wind turbines affect stray voltage on farms in the same way as other electrical gener- ation methods. The way that wind turbines and other generation technologies are connected to the electrical system affects their impact on stray voltage levels. A large wind farm is a very unlikely source of stray voltage because there is no direct connection to the utility distribution system or farm wiring system. Single large turbines and small wind turbines con- nected directly to a distribution system can affect stray voltage levels. Small wind turbines connected directly to farm wiring systems are the most likely type of wind installation to cause stray voltage if not properly wired and inspected. A fact sheet developed by the Midwest Rural Energy Council Wind farms – transmission connection Large wind turbines (>100 kW) are usually plants. These large-scale generation facilities are installed in groups that make up a wind farm. typically owned and operated by electric utilities Turbines in a wind farm typically generate three- or other independent energy suppliers. Wind farms phase power that is delivered to a substation are permitted and regulated by state ordinances and transformer that converts the power to the proper rules. They must follow the same electrical system voltage and connects to a transmission line.
    [Show full text]
  • Stray Voltage Guide MREC 120917
    Stray Voltage Detection A SELF-HELP GUIDE FROm… Midwest Rural Energy Council Table of Contents 2 Introduction ........................................................................................................................3 What is Stray Voltage ........................................................................................................4 Types of Voltage Sources ..................................................................................................4 Causes of Stray Voltage ....................................................................................................4 Stray Voltage Detection ...................................................................................................5 Making Electrical Measurements ....................................................................................6 Recording Voltage Data.....................................................................................................7 Interpreting Voltage Data .................................................................................................7 Monitoring Stray Voltage ..................................................................................................8 Farm Wiring Checklist ......................................................................................................9 Data Collection Form ......................................................................................................10 Mission Statement ............................................................................................................11
    [Show full text]
  • Literature Review and Synthesis of Research Findings on the Impact of Stray Voltage on Farm Operations
    Literature Review and Synthesis of Research Findings on the Impact of Stray Voltage on Farm Operations Prepared by Douglas J. Reinemann, Ph.D. For the Ontario Energy Board 31 March 2008 Disclaimer: The views expressed in this paper are those of Douglas J. Reinemann Ph.D. and do not necessarily represent the views of, and should not be attributed to, the Ontario Energy Board, any individual Board Member, or Board staff. ii Executive Summary This report synthesizes the main findings and conclusions of the body of scientific literature on the potential for tingle voltage (or stray voltage) or at power frequencies (50 to 60 Hz), to directly or indirectly affect farm output or productivity. The report includes: • A review of scientific literature, • A description of the symptoms indicative of the presence of tingle/stray voltage, • Descriptions of the pathways whereby tingle/stray voltage can have an impact on farms, • An indication, by animal type, of the minimum voltage and current level at which impacts on farm operations can be expected, • A description of the on‐farm measures available for mitigating tingle/stray voltage, and • The range of regulatory measures that have been adopted to achieve the objective of ensuring that tingle/stray voltage does not unduly impact farm operations. The direct effect of animal contact with electrical voltage can range from: • Mild behavioral reactions indicative of sensation, to • Involuntary muscle contraction – or twitching, to • Intense behavioral responses indicative of pain, The indirect effects of these behaviors can vary considerably depending on the specifics of the contact location, level of current flow, body pathway, frequency of occurrence, and many other factors related to the daily activities of animals.
    [Show full text]