Han snakket om spesifikk jordmotstand, hva er viktig med den? Bør det måles resistivitet – eller kan det benyttes tabeller for å prosjektere jordingssystemer. Resistivitet vs Global jord. Målinger kan benyttes til å beregne størrelse / omfang på jordelektrode, finne beste plassering for jordelektrode og beregne om området kan defineres som omfattende jordingsnettverk (global jord).
Hvilken betydning har resistivitet for prosjektering av jordelektroder?
Tore Solhaug har mange års erfaring og regnes av mange som en guru innen jordplatemåling. Han vil snakke om betydningen av å kjenne til jordens elektriske ledeevne (resistivitet) for å kunne prosjektere jordelektroder. Resistiviteten i bakken er en viktig faktor for å beregne omfang, beste plassering og forventet overgangsmotstand for jordelektroder. Den har også stor betydning for kvaliteten på impulsjording. I tillegg benyttes resistivitetsverdien til å beregne om et høyspenningsanlegg (for eksempel distribusjonsnett) kan betegnes som Omfattende jordingsnettverk (global jord).
The document outlines the campaign objectives for communicating the European Green Deal to the public. The three main objectives are to: 1) raise awareness of EU action for a more sustainable Europe; 2) trigger public support for EU solutions to the climate and biodiversity crises; and 3) convince citizens to make more sustainable choices. It emphasizes the need to join forces with a wide range of stakeholders and align outreach efforts at the local level to contribute to the success of the European Green Deal project.
This document provides an overview of soil and water conservation engineering. It discusses the status of soil conservation in India, including causes and extent of soil degradation. It outlines 10 topics that will be covered, including the universal soil loss equation, erosion control techniques, water harvesting, and wind erosion. The importance of soil conservation to protect productive lands and prevent damage from droughts and floods is emphasized. Key programs implemented in India to address soil erosion and degradation are also summarized.
This document provides an overview of wind energy, including its history, how wind turbines work, types of wind turbines, factors that determine suitable locations for wind farms, the growth of wind power in Europe, future prospects for offshore wind, pros and cons of wind power, and approaches for building consensus around wind farm projects. Key points covered include the long history of windmill technology, how horizontal and vertical-axis turbines convert kinetic wind energy to electricity, Europe installing over 100,000 megawatts of wind capacity by 2012 to supply 7% of its electricity, and methods for managing social and environmental conflicts related to wind energy development.
Sandia National Laboratories is developing virtual power plant (VPP) technology to help integrate renewable energy into the electric grid. A VPP aggregates distributed energy resources like solar, storage, and demand response to provide grid services normally provided by traditional power plants. Sandia is researching the optimization, control, and cybersecurity of VPPs. In 2017, they will demonstrate a VPP using real hardware at their Distributed Energy Technologies Laboratory. The goal is to increase renewable energy adoption while improving grid reliability and resilience.
Hydroelectric power is generated by harnessing the kinetic energy of flowing water to turn turbines that drive generators to produce electricity. About 20% of the world's electricity comes from hydroelectric power, making it the largest renewable energy source. While hydroelectricity produces no emissions, it can significantly alter river ecosystems by creating reservoirs and forcing relocations of human settlements. Major hydroelectric power stations in the United States include the Grand Coulee Dam in Washington State, Chief Joseph Dam in Washington State, and the Hoover Dam between Arizona and Nevada.
Hi , I am Ruby. I would like to share a ppt on ऊर्जा संरक्षण /Energy Conservation. "Let's NURTURE THE NATURE, SO THAT WE CAN HAVE A BETTER FUTURE". Hope these slide will help you to know better about EnergyConservation.
Environmental sustainability of family farming can be obtained by helping family farms to conserve and ensure the sustainable use of natural resources on their farms, namely water, land and biodiversity.
Hvilken betydning har resistivitet for prosjektering av jordelektroder?
Tore Solhaug har mange års erfaring og regnes av mange som en guru innen jordplatemåling. Han vil snakke om betydningen av å kjenne til jordens elektriske ledeevne (resistivitet) for å kunne prosjektere jordelektroder. Resistiviteten i bakken er en viktig faktor for å beregne omfang, beste plassering og forventet overgangsmotstand for jordelektroder. Den har også stor betydning for kvaliteten på impulsjording. I tillegg benyttes resistivitetsverdien til å beregne om et høyspenningsanlegg (for eksempel distribusjonsnett) kan betegnes som Omfattende jordingsnettverk (global jord).
The document outlines the campaign objectives for communicating the European Green Deal to the public. The three main objectives are to: 1) raise awareness of EU action for a more sustainable Europe; 2) trigger public support for EU solutions to the climate and biodiversity crises; and 3) convince citizens to make more sustainable choices. It emphasizes the need to join forces with a wide range of stakeholders and align outreach efforts at the local level to contribute to the success of the European Green Deal project.
This document provides an overview of soil and water conservation engineering. It discusses the status of soil conservation in India, including causes and extent of soil degradation. It outlines 10 topics that will be covered, including the universal soil loss equation, erosion control techniques, water harvesting, and wind erosion. The importance of soil conservation to protect productive lands and prevent damage from droughts and floods is emphasized. Key programs implemented in India to address soil erosion and degradation are also summarized.
This document provides an overview of wind energy, including its history, how wind turbines work, types of wind turbines, factors that determine suitable locations for wind farms, the growth of wind power in Europe, future prospects for offshore wind, pros and cons of wind power, and approaches for building consensus around wind farm projects. Key points covered include the long history of windmill technology, how horizontal and vertical-axis turbines convert kinetic wind energy to electricity, Europe installing over 100,000 megawatts of wind capacity by 2012 to supply 7% of its electricity, and methods for managing social and environmental conflicts related to wind energy development.
Sandia National Laboratories is developing virtual power plant (VPP) technology to help integrate renewable energy into the electric grid. A VPP aggregates distributed energy resources like solar, storage, and demand response to provide grid services normally provided by traditional power plants. Sandia is researching the optimization, control, and cybersecurity of VPPs. In 2017, they will demonstrate a VPP using real hardware at their Distributed Energy Technologies Laboratory. The goal is to increase renewable energy adoption while improving grid reliability and resilience.
Hydroelectric power is generated by harnessing the kinetic energy of flowing water to turn turbines that drive generators to produce electricity. About 20% of the world's electricity comes from hydroelectric power, making it the largest renewable energy source. While hydroelectricity produces no emissions, it can significantly alter river ecosystems by creating reservoirs and forcing relocations of human settlements. Major hydroelectric power stations in the United States include the Grand Coulee Dam in Washington State, Chief Joseph Dam in Washington State, and the Hoover Dam between Arizona and Nevada.
Hi , I am Ruby. I would like to share a ppt on ऊर्जा संरक्षण /Energy Conservation. "Let's NURTURE THE NATURE, SO THAT WE CAN HAVE A BETTER FUTURE". Hope these slide will help you to know better about EnergyConservation.
Environmental sustainability of family farming can be obtained by helping family farms to conserve and ensure the sustainable use of natural resources on their farms, namely water, land and biodiversity.
Climate Change Adaptation Project (CCAP), "Developing Climate Change Scenarios for Agriculture of Afghanistan", a project implemented for Ministry of Agriculture, Irrigation and Livestock; Afghanistan. It is supported by GEF/UNDP, between August 2016 and May 2017. MgtWell Consulting Services, Kabul was the implementing agency.
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Determinants of Improved Agricultural Technology Adoption in Ethiopia essp2
This document summarizes research on determinants of improved agricultural technology adoption in Ethiopia. The study finds that improved technologies like fertilizer and improved seeds are complements rather than substitutes. Adoption is determined by factors like wealth, education, land size, market access, and extension services. Households with more wealth and education and less distance to markets have higher probabilities of adopting individual technologies and combinations of technologies. Female-headed households adopt improved technologies less than male-headed households.
What is Climate-Smart Agriculture? Background, opportunities and challengesCIFOR-ICRAF
This presentation by Alexandre Meybeck of the FAO was given at a session titled "Using climate-smart technologies to scale up climate-smart agriculture practices" at the Global Landscapes Forum in Lima, Peru, on December 7, 2014.
The panel presentation and discussion focused on how these climate-smart technologies can be scaled-up to benefit smallholder farmers. This was followed by a public debate.
Climate Resilient Agriculture an Approach to Reduce the Ill-Effect of Climate...UditDebangshi
Climate resilient agriculture (CRA) is a sustainable
approach for converting and reorienting agricultural systems to
support food security under the new realities of climate change
through different adaptation and mitigation mechanisms.
Agricultural systems are extremely vulnerable to climate change, given their sensitivity to variations in different threats like temperature, precipitation and incidence of natural events and disasters such as droughts and floods with this on an average the extreme weather patterns can impact farm incomes in the range of 15-18 %. Threats can be reduced by increasing the adaptive capacity of farmers as well as increasing resilience and resource use efficiency in agricultural production systems. CRA promotes synchronized actions by farmers, government, scientist, private sector, and policy-makers through three main action areas: (1) Building the capacity to identify the threats; (2) Curing the threats through adaptation and mitigation process (3) Sustain their adaptive mechanisms over a long time. The vulnerability of existing conditions of poverty, malnutrition and increasing populations puts intense pressure on finite natural resources, especially land, water and energy – all of which are integral to agricultural systems. In this context, it becomes imperative to adopt Climate-Resilient Agriculture (CRA) measures at cooperative scale to address the impending impact of climate change on agriculture.
This document provides information about extensive farming. It defines extensive farming as an agricultural system that uses small amounts of inputs like labor, fertilizers, and capital relative to the land area. It notes extensive farming commonly refers to sheep and cattle farming on less productive land but also large-scale grain crops. Advantages include lower labor needs, ability to mechanized over large flat areas, and lower input costs. Disadvantages include typically lower yields than intensive farming and large land requirements limiting wildlife.
B Sc Agri II Agricultural Extansion Unit 4 Women Development ProgrammesRai University
1. The document discusses several programs aimed at developing women and children in rural areas of India, including the Development of Women and Children in Rural Areas (DWCRA) program, the Integrated Child Development Scheme (ICDS), and the Mahila Samridhi Yojana (MSY).
2. It also discusses the Reorganized Extension System (T&V System) introduced in 1974 with World Bank assistance to improve the transfer of agricultural technology to farmers through contact farmers.
3. The key features of the T&V System included professionalism, a single line of command, concentration of effort, time-bound work, field and farmer orientation, regular training, and linkages with research.
This document discusses various renewable energy sources including solar energy, wind power, hydropower, biomass, geothermal, and fuel cells. It defines renewable energy as energy from naturally replenished resources like sunlight, wind, rain, tides, and geothermal heat. The document describes different types of renewable technologies and provides examples of their use, such as large wind farms that generate electricity from turbines or home wind turbines that power individual residences. Biomass energy from organic waste is another significant renewable source. Fuel cells are also covered but only considered renewable if powered by renewable fuels like hydrogen produced from water.
Elkomp 2024 - Spenningsprøving og tilstandskontroll av høyspentkabler med VLF...Trainor Elsikkerhet AS
• Spenningsprøving av kabler med VLF
• Relevante standarder for VLF
• Tilstandskontroll med VLF
✦ VLF TD test for TanDelta
✦ VLF PD test for glimming (partial discharge)
• VLF systemer fra B2 ELECTRONIC
- 41 utdannede piloter og 5 under opplæring
- Rundt 1000 flytimer og 5100 flighter siden
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- 408 flytimer og 1740 flighter i 2023
- Ingen alvorlige hendelser
- 2 mindre alvorlige hendelser
Elkomp 2024 - Elbillading med energilagring for å balansere strømnettet Nils ...Trainor Elsikkerhet AS
The roadblock to a greener future
Lack of electrical power…
> Where you need it
> When you need it
> The amount you need
…is slowing down the
electrification of transportation
Elkomp 2024 - Luftledninger over 1 kV – NEK 445 Lars Jakob Paulsen, Fagsjef h...Trainor Elsikkerhet AS
• NEK standard
• Hvem er NK 11 og hva jobber de med
• Hva skjer i internasjonal standardisering
• NEK 445 og pågående arbeid med
Nasjonale Normative forhold (NNA)
Elkomp 2024 - Forskrift om elektriskeforsyningsanlegg - Frode Kyllingstad DSBTrainor Elsikkerhet AS
Forskrift om
elektriskeforsyningsanlegg
Elsikkerhetskompetanse
Trainor, Tønsberg
Mars 2023
Frode Kyllingstad 14. mars 2024
Sjefingeniør
Elsikkerhetsseksjonen
Climate Change Adaptation Project (CCAP), "Developing Climate Change Scenarios for Agriculture of Afghanistan", a project implemented for Ministry of Agriculture, Irrigation and Livestock; Afghanistan. It is supported by GEF/UNDP, between August 2016 and May 2017. MgtWell Consulting Services, Kabul was the implementing agency.
What practical steps can smallholder farmers take to adapt their agricultural practices to secure dependable food supplies and livelihoods? And can they do this while also decreasing greenhouse gas emissions or increasing carbon sequestration, thereby decreasing future climate change?
Determinants of Improved Agricultural Technology Adoption in Ethiopia essp2
This document summarizes research on determinants of improved agricultural technology adoption in Ethiopia. The study finds that improved technologies like fertilizer and improved seeds are complements rather than substitutes. Adoption is determined by factors like wealth, education, land size, market access, and extension services. Households with more wealth and education and less distance to markets have higher probabilities of adopting individual technologies and combinations of technologies. Female-headed households adopt improved technologies less than male-headed households.
What is Climate-Smart Agriculture? Background, opportunities and challengesCIFOR-ICRAF
This presentation by Alexandre Meybeck of the FAO was given at a session titled "Using climate-smart technologies to scale up climate-smart agriculture practices" at the Global Landscapes Forum in Lima, Peru, on December 7, 2014.
The panel presentation and discussion focused on how these climate-smart technologies can be scaled-up to benefit smallholder farmers. This was followed by a public debate.
Climate Resilient Agriculture an Approach to Reduce the Ill-Effect of Climate...UditDebangshi
Climate resilient agriculture (CRA) is a sustainable
approach for converting and reorienting agricultural systems to
support food security under the new realities of climate change
through different adaptation and mitigation mechanisms.
Agricultural systems are extremely vulnerable to climate change, given their sensitivity to variations in different threats like temperature, precipitation and incidence of natural events and disasters such as droughts and floods with this on an average the extreme weather patterns can impact farm incomes in the range of 15-18 %. Threats can be reduced by increasing the adaptive capacity of farmers as well as increasing resilience and resource use efficiency in agricultural production systems. CRA promotes synchronized actions by farmers, government, scientist, private sector, and policy-makers through three main action areas: (1) Building the capacity to identify the threats; (2) Curing the threats through adaptation and mitigation process (3) Sustain their adaptive mechanisms over a long time. The vulnerability of existing conditions of poverty, malnutrition and increasing populations puts intense pressure on finite natural resources, especially land, water and energy – all of which are integral to agricultural systems. In this context, it becomes imperative to adopt Climate-Resilient Agriculture (CRA) measures at cooperative scale to address the impending impact of climate change on agriculture.
This document provides information about extensive farming. It defines extensive farming as an agricultural system that uses small amounts of inputs like labor, fertilizers, and capital relative to the land area. It notes extensive farming commonly refers to sheep and cattle farming on less productive land but also large-scale grain crops. Advantages include lower labor needs, ability to mechanized over large flat areas, and lower input costs. Disadvantages include typically lower yields than intensive farming and large land requirements limiting wildlife.
B Sc Agri II Agricultural Extansion Unit 4 Women Development ProgrammesRai University
1. The document discusses several programs aimed at developing women and children in rural areas of India, including the Development of Women and Children in Rural Areas (DWCRA) program, the Integrated Child Development Scheme (ICDS), and the Mahila Samridhi Yojana (MSY).
2. It also discusses the Reorganized Extension System (T&V System) introduced in 1974 with World Bank assistance to improve the transfer of agricultural technology to farmers through contact farmers.
3. The key features of the T&V System included professionalism, a single line of command, concentration of effort, time-bound work, field and farmer orientation, regular training, and linkages with research.
This document discusses various renewable energy sources including solar energy, wind power, hydropower, biomass, geothermal, and fuel cells. It defines renewable energy as energy from naturally replenished resources like sunlight, wind, rain, tides, and geothermal heat. The document describes different types of renewable technologies and provides examples of their use, such as large wind farms that generate electricity from turbines or home wind turbines that power individual residences. Biomass energy from organic waste is another significant renewable source. Fuel cells are also covered but only considered renewable if powered by renewable fuels like hydrogen produced from water.
Elkomp 2024 - Spenningsprøving og tilstandskontroll av høyspentkabler med VLF...Trainor Elsikkerhet AS
• Spenningsprøving av kabler med VLF
• Relevante standarder for VLF
• Tilstandskontroll med VLF
✦ VLF TD test for TanDelta
✦ VLF PD test for glimming (partial discharge)
• VLF systemer fra B2 ELECTRONIC
- 41 utdannede piloter og 5 under opplæring
- Rundt 1000 flytimer og 5100 flighter siden
våren 2019
- 408 flytimer og 1740 flighter i 2023
- Ingen alvorlige hendelser
- 2 mindre alvorlige hendelser
Elkomp 2024 - Elbillading med energilagring for å balansere strømnettet Nils ...Trainor Elsikkerhet AS
The roadblock to a greener future
Lack of electrical power…
> Where you need it
> When you need it
> The amount you need
…is slowing down the
electrification of transportation
Elkomp 2024 - Luftledninger over 1 kV – NEK 445 Lars Jakob Paulsen, Fagsjef h...Trainor Elsikkerhet AS
• NEK standard
• Hvem er NK 11 og hva jobber de med
• Hva skjer i internasjonal standardisering
• NEK 445 og pågående arbeid med
Nasjonale Normative forhold (NNA)
Elkomp 2024 - Forskrift om elektriskeforsyningsanlegg - Frode Kyllingstad DSBTrainor Elsikkerhet AS
Forskrift om
elektriskeforsyningsanlegg
Elsikkerhetskompetanse
Trainor, Tønsberg
Mars 2023
Frode Kyllingstad 14. mars 2024
Sjefingeniør
Elsikkerhetsseksjonen
Viktige endringer i EN 50110-1: 2023
• Hva medfører dette i praksis for bransjen
• Sammenhengen mellom FSE og EN 50110-1
• Viktige definisjoner
• Arbeidsmetodikk
• 2-polet spenningstesting
• Krav til personell
4. Spesifikk jordmotstand
Hva er viktig med den?
• Jordelektrodens egenskaper påvirkes av grunnforholdene
• Bør det måles resistivitet – eller kan det benyttes tabeller for å
prosjektere jordingssystemer
• Resistivitet vs Global jord
5
5. Jordresistivitet
• Hvordan kan vi vite at vi vite at vi velger riktig jordart?
• Tabellverdier er svært omtrentlige
– Resistiviteten varierer med fuktighetsgrad i bakken
Type jordsmonn Resistivitetsverdier
Finkornet sand 150-2000 ohm cm
Jord (matjord, myr, torv) 5-500 ohm cm
Leire 5-200 ohm cm
Kritt (kalkholdig jord) 50-3000 ohm cm
Skifer 200-50000 ohm cm
Granitt >1 000 000 ohm cm
5
6. Jordresistivitet
(Spesifikk jordmotstand)
Målinger kan benyttes til å
• beregne størrelse/omfang på jordelektrode
• beregne motstandsverdi for elektrode
• finne beste plassering for jordelektrode
• beregne om området kan defineres som
omfattende jordingsnettverk (global jord)
6
7. Jordresistivitet
Fra FEF:2006, §4-11 heter det:
• Tillatt berøringsspenning UTP i figur 4-2 ansees være overholdt dersom
en av følgende forutsetninger er oppfylt:
– Jordingsanlegget er en del av et utbredt jordingssystem
– Jordpotensialhevningen UE ved jordfeil skal ikke overstige 2 ganger
tillatt berøringsspenning
– Jordpotensialhevningen UE ved jordfeil skal ikke overstige 4 ganger
tillatt berøringsspenning, samtidig som det er gjennomført tiltak
beskrevet under avsnittet «Tiltak for å redusere
berøringsspenning» skal være iverksatt
Dersom disse forutsetningene ikke er oppfylt, skal den reelle
berøringsspenningen beregnes eller måles.
8
14. Jordresistivitet
R = motstand målt i ohm
a = avstanden mellom spydene målt i cm eller meter
ρ = resistiviteten til en dybde lik «a» referert i cm
eller meter
𝜌 = 2𝜋𝑎𝑅
a
aaa
a
a
20
C1
P1
P2
C2
14
15. Etablering av sammensatte elektroder
• Ved flere jordspyd
• 𝑎 = 1,5𝑑
a
d
𝑅 =
𝜌
2 𝑥 𝜋 𝑥 𝐿
x (ln
4 𝑥 𝐿
𝑟
-1) x 1,25 x ant.spyd
14
17. Jordresistivitet
• Viktig å huske på:
• Dersom elektroden ikke ligger frostfritt vil
overgangsmotstand for den etablerte elektrode variere
med årstidene
• Høyest resistivitet og overgangsmotstand i frostmark
17
18. Jordresistivitet
• Beregne et utbredt jordingssystem (Global jord)
• Beregne nødvendig omfang og plassering av jordelektrode
• Beregne antatt tillatt berøringsspenning UTp (tf)
17
19. Jordresistivitet
Hva kan målingene benyttes til ?
Fra FEF:2006, §4-11 heter det:
• Tillatt berøringsspenning UTP i figur 4-2 ansees være overholdt dersom
en av følgende forutsetninger er oppfylt:
– Jordingsanlegget er en del av et utbredt jordingssystem
– Jordpotensialhevningen UE ved jordfeil skal ikke overstige 2 ganger
tillatt berøringsspenning
– Jordpotensialhevningen UE ved jordfeil skal ikke overstige 4 ganger
tillatt berøringsspenning, samtidig som det er gjennomført tiltak
beskrevet under avsnittet «Tiltak for å redusere
berøringsspenning» skal være iverksatt
Dersom disse forutsetningene ikke er oppfylt, skal den reelle
berøringsspenningen beregnes eller måles.
18
21. Beregning av antatt tillatt berøringsspenning
21
𝑈 𝑇𝑃(𝑡𝑓)=UT (tf)+(RF1+RF2)xIB
RF2 = 1,5m-1 x ρ
22. Oppsummering
• Resistivitetsmålinger er mer presise enn
tabeller
• Kan benyttes til viktige beregninger
- i forbindelse med etablering av elektroder
- for å etablere tilleggsjord
- beregne Global jord
- beregne berøringsspenninger
22
Benevnelsen er Ohm multiplisert med lengde (cm eller meter)
Ved utregning/kalkulasjoner er det viktig å flytte komma korrekt
Pkt 2: I fall bruk av tabeller – hvilken verdi i tabellen skal vi benytte?
Det finnes mange tabeller for resistivitet, der de fleste er svært upresise.
Anbefaler å måle for å få eksakt verdi som kan benyttes i beregninger av elektroder.
Hvis vi bestemmer oss for å måle, kan disse benyttes til…
Benevnelsen er Ohm multiplisert med lengde (cm eller meter)
Ved utregning/kalkulasjoner er det viktig å flytte komma korrekt
- Dersom det kan dokumenteres at jordelektroden er en del av et utbredt jordingssystem, er det ikke krav til å måle overgangsmotstand. For å vurdere om området kan betraktes som «Global jord» trengs det å kjenne til områdets gjennomsnittlige resistivitetsverdi.
Typisk for Global jord kan være en hyttegrend, med omfattende jordingsnettverk
Gjennomsnittlig jordresistivitet betyr at det må foretas representativt antall resistivitetsmålinger for den dybden i bakken som jordledere og elektroder er etablert
Det benyttes en gjennomsnittlig verdi for beregninger.
- Ved å beregne den gjennomsnittlige motstanden for arealet, kan vi finne Jordpotensialhevingen UE, når vi kjenner til 1-polet jordslutningsstrøm
Måling kan gi store gevinster både teknisk og økonomisk.
Undersøkelser i område med etablert elektrode der det er behov for tilleggsjord
Viktige elementer vi må ha klarhet i for å prosjektere elektrodesystemet
Skal tilfredsstille kravene til berøringsspenning
Avstanden «a» er lik dybden ned i bakken som måles.
- Andre formler for ringjord, strålejord og kombinerte elektrodeformer (eks. kKråkefot)
- Formel beregner den forventede overgangsmotstand for elektroden når denne er etablert.
Riktig plassering av jordelektrode kan redusere verdien for overgangsmotstand betraktelig
Viktig å huske på at dersom elektroden skal fungere både som berøringsbeskyttelse og impulsjord, må avstanden fra elektroden til det den skal beskytte ikke være for stor (helst rett under).
Oppsummering av resistivitet
Når ingen av de 3 første betingelsene er oppfylt, må den reelle berøringsspenningen UT beregnes eller måles
Resistiviteten har innvirkning på tilleggsimpedansen ved beregning av antatt tillatt berøringsspenning
Kan benyttes når det ikke er mulig å måle/beregne berøringsspenninger på annen måte.