scholarly journals PENGARUH KELEMBABAN TANAH TERHADAP TAHANAN PENTANAHAN STUDI KASUS PADA GARDU INDUK KEMAYORAN 150 kV

2020 ◽  
Vol 3 (1) ◽  
pp. 18-23
Author(s):  
Rahmawati Fajri Latiefa ◽  
Irzan Zakir ◽  
Massus Subekti
Keyword(s):  
Soil Moisture ◽  
Soil Condition ◽  
Soil Conditions ◽  
Grid System ◽  
Actual Measurement ◽  
Grounding System ◽  
Grounding Resistance ◽  
The Earth ◽  
System Method ◽  
Dry Soil

Abstract The value of grounding resistance at the substation should be 0 Ω or less than 1 Ω. The value of grounding resistance is influenced by the resistivity and the grounding system method used. the resistivity is influenced by external factors, one of which is the soil moisture. The purpose of this research are (i) to find the effect of soil moisture to grounding resistance with; (a) compare the actual measurements of grounding resistance between wet soil conditions and dry soil conditions; (b) compare actual measurement results, manual calculations, and ETAP 12.6 software on grid resistance between wet soil conditions and dry soil conditions. (ii) to find the effect that would occur if the grounding station resistance exceeds the IEEE Std 80-2000 standard value of less than 1 Ω. The research method is comparative quantitative. This research is measuring grounding resistance with driven rood system and with grid system during wet and dry soil conditions, and then calculate grid resistance of Kemayoran 150 kV Substation in dry and wet soil conditions using manual calculating based on IEEE Std 80 -2000, and calculating using ETAP 12.6 software. The result of measument grounding resistance with driven rood system show the value of grounding resistance is 27,72 Ω when dry soil condition and 18,92 Ω when wet soil condition, the measurement result of grounding resistance with grid system show the value of grounding resistance is 0.076 Ω when the soil condition is dry and 0.049 Ω during wet soil conditions, the manual calculation of grid resistance is 0.078 Ω for dry soil conditions and 0.056 Ω, and the ETAP calculation of grid resistance is 0.071 Ω for dry soil conditions and 0.051 Ω for wet soil conditions. Based on the results of this research, the conclusion is soil moisture can affect the value of grounding resistance, based on this research the dry soil condition of the earth resistance value is higher than the wet soil conditions. The value of earthquake grounding shall be less than 1 Ω due to minimize the earth potenial value (Ground Potensial Rise) which can cause dangerous voltage for humans. Abstrak Nilai tahanan pentaahan pada Gardu Induk harus mendekati 0 Ω atau kurang dari 1 Ω, dan dipengaruhi oleh tahanan jenis tanah dan metode sistem pentanahan yang digunakan. Tahanan jenis tanah dipengaruhi oleh faktor eksternal, salah satunya adanya kelembaban tanah. Tujuan dari penelitian ini adalah mengetahui pengaruh kelembaban tanah terhadap nilai tahanan pentanahan, dan mengetahui pengaruh yang akan terjadi jika tahanana pentanahan gardu induk melebihi nilai standar IEEE Std 80-2000 yaitu kurang dari 1 Ω. Penelitian ini melakukan pengukuran aktual tahanan pentanahan dengan sistem driven rood dan tahanan pentanahan dengan sistem grid saat kondisi tanah basah dan tanah kering, serta perhitungan tahanan pentanhan grid Gardu Induk Kemayoran 150 kV dalam kondisi tanah kering dan tanah basah dengan menggunakan perhitungan manual berdasarkan IEEE Std 80-2000, dan perhitungan menggunakan software ETAP 12.6. Dalam penelitian ini ditemukan bahwa kelembaban tanah dapat mempengaruhi nilai tahanan pentanahan, dengan berdasarkan saat kondisi tanah kering nilai tahanan pentanahan lebih tinggi dibandingkan saat kondisi tanah basah Hasil pengukuran tahanan pentanahan dengan sistem driven rood menunjukkan nilai tahanan pentanahan adalah 27,72 Ω saat kondisi tanah kering dan 18,92 Ω saat kondisi tanah basah, hasil pengukuran tahanan pentanahan dengan sistem grid menunjukkan nilai tahanan pentanahan adalah 0,076 Ω saat kondisi tanah kering dan 0,049 Ω saat kondisi tanah basah, hasil perhitungan manual tahanan grid adalah 0,078 Ω untuk kondisi tanah kering dan 0,056 Ω, dan hasil perhitungan ETAP tahanan grid adalah 0,071 Ω untuk kondisi tanah kering dan 0,051 Ω untuk kondisi tanah basah.

scholarly journals White Root Rot of Raspberries

1951 ◽  
Vol 4 (3) ◽  
pp. 211
Author(s):  
GC Wade
Keyword(s):  
Soil Moisture ◽  
Root Rot ◽  
Soil Moisture Content ◽  
Soil Conditions ◽  
Causal Organism ◽  
White Root Rot ◽  
High Soil Moisture ◽  
High Soil ◽  
Soil Temperatures ◽  
Dry Soil

The disease known as white root rot affects raspberries, and to a less extent loganberries, in Victoria. The causal organism is a white, sterile fungus that has not been identified. The disease is favoured by dry soil conditions and high soil temperatures. It spreads externally to the host by means of undifferentiated rhizomorphs; and requires a food base for the establishment of infection. The spread of rhizomorphs through the soil is hindered by high soil moisture content and consequent poor aeration of the soil.

scholarly journals Earthworms are little affected by reduced soil tillage methods in vineyards

2017 ◽  
Vol 63 (No. 6) ◽  
pp. 257-263 ◽  
Author(s):  
Faber Florian ◽  
Wachter Elisabeth ◽  
Zaller Johann G
Keyword(s):  
Soil Moisture ◽  
Soil Temperature ◽  
Soil Tillage ◽  
Soil Conditions ◽  
Reduced Tillage ◽  
No Tillage ◽  
Dry Soil ◽  
The Impact ◽  
Tillage Methods ◽  
Erosion Prevention

Inter-rows in vineyards are commonly tilled in order to control weeds and/or to conserve water. While impacts of tillage on earthworms are well studied in arable systems, very little is known from vineyards. In an experimental vineyard, the impact of four reduced tillage methods on earthworms was examined: rotary hoeing, rotary harrowing, grubbing and no tillage. According to an erosion prevention programme, tillage was applied every other inter-row only while alternating rows retained vegetated. Earthworms were extracted from the treated inter-rows 10, 36, 162 and 188 days after tillage. Across dates, tillage methods had no effect on overall earthworm densities or biomass. Considering each sampling date separately, earthworm densities were affected only at day 36 after tillage leading to lower densities under rotary hoeing (150.7 ± 42.5 worms/m<sup>2</sup>) and no tillage (117.3 ± 24.8 worms/m<sup>2</sup>) than under rotary harrowing (340.0 ± 87.4 worms/m<sup>2</sup>) and grubbing (242.7 ± 43.9 worms/m<sup>2</sup>). Time since tillage significantly increased earthworm densities or biomass, and affected soil moisture and temperature. Across sampling dates, earthworm densities correlated positively with soil moisture and negatively with soil temperature; individual earthworm mass increased with increasing time since tillage. It was concluded that reduced tillage in vineyards has little impact on earthworms when applied in spring under dry soil conditions.

scholarly journals Evidence for enhanced infiltration of ion load during snowmelt

2010 ◽  
Vol 7 (1) ◽  
pp. 1431-1457
Author(s):  
G. Lilbæk ◽  
J. W. Pomeroy
Keyword(s):  
Soil Moisture ◽  
Infiltration Rate ◽  
Frozen Soil ◽  
Ion Concentration ◽  
Soil Conditions ◽  
Ion Concentrations ◽  
Infiltration Rates ◽  
Dry Soil ◽  
Infiltration Excess ◽  
The Impact

Abstract. Meltwater ion concentration and infiltration rate into frozen soil both decline rapidly as snowmelt progresses. Their temporal association is highly non-linear and a covariance term must be added in order to use time-averaged values of snowmelt ion concentration and infiltration rate to calculate chemical infiltration. The covariance is labelled enhanced infiltration and represents the additional ion load that infiltrates due to the timing of high meltwater concentration and infiltration rate. Previous assessment of the impact of enhanced infiltration has been theoretical; thus, experiments were carried out to examine whether enhanced infiltration can be recognized in controlled laboratory settings and to what extent its magnitude varies with soil moisture. Three experiments were carried out: dry soil conditions, unsaturated soil conditions, and saturated soil conditions. Chloride solution was added to the surface of frozen soil columns; the concentration decreased exponentially over time to simulate snow meltwater. Infiltration excess water was collected and its chloride concentration and volume determined. Ion load infiltrating the frozen soil was specified by mass conservation. Results showed that infiltrating ion load increased with decreasing soil moisture as expected; however, the impact of enhanced infiltration increased considerably with increasing soil moisture. Enhanced infiltration caused 2.5 times more ion load to infiltrate during saturated conditions than that estimated using time-averaged ion concentrations and infiltration rates alone. For unsaturated conditions, enhanced infiltration was reduced to 1.45 and for dry soils to 1.3. Reduction in infiltration excess ion load due to enhanced infiltration increased slightly (2–5%) over time, being greatest for the dry soil (45%) and least for the saturated soil (6%). The importance of timing between high ion concentrations and high infiltration rates was best illustrated in the unsaturated experiment, which showed large inter-column variation in enhanced ion infiltration due to variation in this temporal covariance.

scholarly journals Optimization of substation grounding grid design for horizontal and vertical multilayer and uniform soil condition using Simulated Annealing method

PLoS ONE ◽  
2021 ◽  
Vol 16 (9) ◽  
pp. e0256298
Author(s):  
Navinesshani Permal ◽  
Miszaina Osman ◽  
Azrul Mohd Ariffin ◽  
Navaamsini Boopalan ◽  
Mohd Zainal Abidin Ab Kadir
Keyword(s):  
Simulated Annealing ◽  
Soil Structure ◽  
Soil Layer ◽  
Minimum Cost ◽  
Soil Condition ◽  
Problem Formulation ◽  
Soil Conditions ◽  
Grounding System ◽  
Grounding Grid ◽  
Grounding Grids

Grounding systems are critical in safeguarding people and equipment from power system failures. A grounding system’s principal goal is to offer the lowest impedance path for undesired fault current. Optimization of the grounding grid designs is important in satisfying the minimum cost of the grounding system and safeguarding those people who work in the surrounding area of the grounded installations. Currently, there is no systematic guidance or standard for grounding grid designs that include two-layer soil and its effects on grounding grid systems, particularly vertically layered soil. Furthermore, while numerous studies have been conducted on optimization, relatively limited study has been done on the problem of optimizing the grounding grid in two-layer soil, particularly in vertical soil structures. This paper presents the results of optimization for substation grounding systems using the Simulated Annealing (SA) algorithm in different soil conditions which conforms to the safety requirements of the grounding system. Practical features of grounding grids in various soil conditions discussed in this paper (uniform soil, two-layer horizontal soil, and two-layer vertical soil) are considered during problem formulation and solution algorithm. The proposed algorithm’s results show that the number of grid conductors in the X and Y directions (Nx and Ny), as well as vertical rods (Nr), can be optimized from initial numbers of 35% for uniform soil, 57% for horizontal two-layer soil for ρ1> ρ2, and 33% for horizontal two-layer soil for ρ1< ρ2, and 29% for vertical two-layer soil structure. In other words, the proposed technique would be able to utilize square and rectangle-shaped grounding grids with a number of grid conductors and vertical rods to be implemented in uniform, two-layer horizontal and vertical soil structure, depending on the resistivity of the soil layer.

Grounding System Installation

2018 ◽  
pp. 124-157
Keyword(s):  
Stainless Steel ◽  
Seasonal Variation ◽  
Life Expectancy ◽  
Chemical Treatment ◽  
Annual Cost ◽  
Soil Treatment ◽  
Grounding System ◽  
Grounding Resistance ◽  
The Earth ◽  
Steel Electrodes

This chapter includes the following points: Methods of installing ground rods, chemical ground rod, chemical treatment of soil lessens seasonal variation of electrodes, soil treatment, trench method of soil treatment, lengthen of the earth electrode in the earth, use multiple rods, Ground Enhancement Material, (GEM), grid installation and conductor materials of grounding system. This chapter draws attention also to the following points: ground rod life expectancy, ground rod annual cost, grounding rods accessories and applications, grounding rods installation methods, chemical grounding rods, copper versus stainless steel electrodes, variation on grounding resistance system by seasonal variation effects and finally how to improve the earthing resistance.

Measurement of the influence of low water availability on the productivity of Agave weberi cultivated under controlled irrigation

2014 ◽  
Vol 94 (2) ◽  
pp. 439-444 ◽  
Author(s):  
Steven J. Bergsten ◽  
J. Ryan Stewart
Keyword(s):  
Soil Moisture ◽  
Nutrient Uptake ◽  
Water Availability ◽  
Irrigation System ◽  
Biomass Accumulation ◽  
Dry Weight ◽  
Energy Crop ◽  
Soil Conditions ◽  
Controlled Irrigation ◽  
Dry Soil

Bergsten, S. J. and Stewart, J. R. 2014. Measurement of the influence of low water availability on the productivity of Agave weberi cultivated under controlled irrigation. Can. J. Plant Sci. 94: 439–444. In recent years, research has focused on determining the potential of Agave to be utilized for bioenergy production due to its ability to grow in arid and marginal lands. However, little is known regarding its productivity under limited water conditions. Most Agave species can tolerate low soil-moisture levels, but it is unclear at what point productivity will be significantly constrained. Using an automated irrigation system under greenhouse conditions, we evaluated the effects of low to high volumetric water content (VWC) levels on biomass accumulation and nutrient uptake of a putative bioenergy crop, Agave weberi. Plants were exposed to four constant VWC levels (0.05, 0.12, 0.19, and 0.26 m3 m−3). Shoot dry weight of plants in the 0.26 m3 m−3 treatment was significantly higher than those in the 0.05 m3 m−3 treatment, but not than those in the intermediate treatments. Both chlorophyll count and nutrient uptake decreased as VWC level decreased. Although plants were fairly productive under moderately dry soil conditions, it would be expected that over time, plants receiving high levels of irrigation would have greater growth than plants in dry soil moisture levels. However, similar yields between the well-watered and moderately dry treatments suggest that A. weberi should be further evaluated as a candidate energy crop in more long-term field trials.

Influence of Soil Temperature and Moisture on Terbutryn Activity and Persistence

Weed Science ◽  
1974 ◽  
Vol 22 (6) ◽  
pp. 571-574 ◽  
Author(s):  
Chu-Huang Wu ◽  
P. W. Santelmann ◽  
J. M. Davidson
Keyword(s):  
Soil Moisture ◽  
Soil Temperature ◽  
Incubation Temperature ◽  
Sandy Loam ◽  
Distribution Coefficients ◽  
Measured Parameter ◽  
Soil Conditions ◽  
Soil Temperatures ◽  
Dry Soil ◽  
Soil Temperature And Moisture

The phytotoxicity of soil-applied terbutryn [2-(tert-butylamino)-4-(ethylamino)-6-(methylthio)-s-triazine] to wheat (Triticum aestivumVill.) was significantly affected by soil moisture and soil temperature. Distribution coefficients (Kd) provided a better indication of the phytotoxicity of terbutryn to wheat than any single measured parameter contributing to herbicide adsorption by the soil. Soil temperatures and soil moisture levels suitable for good plant growth tended to enhance the phytotoxicity of terbutryn. No phytotoxic levels of terbutryn to wheat were detected in Teller sandy loam after 20 weeks of incubation at above 10C and 14% soil moisture by weight. However, phytotoxicity to wheat was observed in air-dry terbutryntreated soil after an incubation period of 20 weeks, regardless of incubation temperature. Significant quantities of terbutryn may remain in the field under dry soil conditions.

scholarly journals Pengembangan Sistem Penangkal Petir dan Pentanahan Elektroda Rod dan Plat

2016 ◽  
Vol 3 (2) ◽  
pp. 66
Author(s):  
Makmur Saini ◽  
A.M. Shiddiq Yunus ◽  
Andareas Pangkung
Keyword(s):  
Transmission Lines ◽  
Private Property ◽  
Soil Conditions ◽  
Moist Soil ◽  
Grounding System ◽  
Grounding Resistance ◽  
High Rise ◽  
Specific Objective ◽  
Dry Conditions ◽  
Electrode Plate

The specific objective of this research is to producea system of internallightning and Eksternal lightning rod withgrounding which has been widely used in industries such aslightning protection and grounding system of substation,transmission lines and coupling wire used in high-rise buildingseither belong to government or private property. In this study,lightning rod is located outside the building structure that servesto catch or receive the bolt of lightning and the lightning deliverto the ground safely. In this study there were 5 different depths ofelectrode rod; 3 m, 5 m, 7 m, 9 m, and 12 m, moreover, 5 widevariety of electrode plate that are 1 x 1 m2, 0.75 x 0.75 m2, 0.5 x0.5 m2, 0.35 x 0.35 m2, 0.25 x 0.25 m2. For grounding electrode rod with a depth of 3 m, 5 m, 7 m, 9 m, 12 m in dry conditions grounding resistance values obtained ranged from 1.55 to 2.03 Ohm. For moist soil conditions, grounding resistance values obtained ranged from 2.21 to 2.60 Ohm. For wet soil conditions grounding resistance values obtained ranged from 1.97 to 2.34 Ohm. For grounding plate, R11 and R12 on the dry conditions grounding resistance values obtained ranged from 2.08 to 2.45 Ohm. For moist soil conditions grounding resistance values obtained ranged from 1.88 to 2.18 Ohm. For wet soil conditions grounding resistance values obtained ranged from 1.55 to 2.06 Ohm. On the external lightning rod with two added electrodes with a depth of 12 m and then connected in parallel with the electrode plate to get the smallest value of grounding resistance in accordance with the standards prescribed.

scholarly journals Diurnal Variation of Convective Activity and Precipitable Water around Ulaanbaator, Mongolia, and the Impact of Soil Moisture on Convective Activity during Nighttime

2008 ◽  
Vol 136 (4) ◽  
pp. 1401-1415 ◽  
Author(s):  
Hiroyuki Iwasaki ◽  
Tomoki Nii ◽  
Tomonori Sato ◽  
Fujio Kimura ◽  
Kiyotaka Nakagawa ◽  
...  
Keyword(s):  
Soil Moisture ◽  
Water Vapor ◽  
Diurnal Variation ◽  
Deep Convection ◽  
Precipitable Water ◽  
The Other ◽  
Soil Conditions ◽  
Convective Activity ◽  
Unstable Condition ◽  
Dry Soil

Abstract The diurnal variations of convective activity and precipitable water were investigated using a C-band airport radar and GPS receivers around Ulaanbaator (UB), Mongolia; this location was considered as an example of an arid region. The convective activity exhibited a pronounced diurnal cycle; it increased rapidly at 1100 local solar time (LST; 0300 UTC), reached the maximum at 1400 LST, and almost disappeared after 1900 LST. On the other hand, no diurnal variation of precipitable water could be observed, which implied that there was no considerable evapotranspiration, and the diurnal variation of the convective activity was irrelevant to the variation of water vapor. The reason why the deep convection could not develop at night is discussed using numerical modeling from the viewpoint of soil moisture. In the moist soil conditions assumed for humid simulations, an increase in the water vapor in the boundary layer due to evapotranspiration led to a potentially unstable condition that was sustained until night. Deep convection was formed at the southern foot of mountains where topographical convergence was expected. On the other hand, in the dry soil conditions assumed for the arid simulations, deep convection did not occur during nighttime even though topographical convergence was expected over the southern foot of the mountains. These features of dry soil conditions were consistent with the results from radar observations around UB. In other words, since the soil around UB is too dry in practice to sustain an unstable condition until night, the deep convection had to decay by night and could not be initiated at night.

scholarly journals Production, stability and degradation of Trichoderma gliotoxin in growth medium, irrigation water and agricultural soil

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
R. Jayalakshmi ◽  
R. Oviya ◽  
K. Premalatha ◽  
S. T. Mehetre ◽  
M. Paramasivam ◽  
...  
Keyword(s):  
Soil Moisture ◽  
Growth Medium ◽  
Growth Phase ◽  
Irrigation Water ◽  
Soil Conditions ◽  
Sterile Soil ◽  
High Soil Moisture ◽  
High Soil ◽  
Unsterile Soil ◽  
Dry Soil

AbstractGliotoxin produced by Trichoderma virens is inhibitory against various phytopathogenic fungi and bacteria. However, its stability in soil-ecosystem has not yet been well-defined. This study aimed to decipher its persistence and behaviour in growth media, irrigation water and soil ecosystems. Gliotoxin production was noticed at logarithmic growth phase and converted into bis-thiomethyl gliotoxin at late stationary growth phase of T. virens in acidic growth medium. But, no gliotoxin production was observed in neutral and alkaline growth medium. Gliotoxin was stable for several days in acidic water but degraded in alkaline water. Degradation of gliotoxin was more in unsterile soil than sterile soil and also that was higher under wet soil than dry soil. Degradation of gliotoxin was hastened by alkaline pH in wet soil but not in dry soil. Under unsterile soil conditions, high soil moisture increased the degradation of gliotoxin and the degradation of gliotoxin occurred quickly in alkaline soil (in 5 days) compared to acidic soil (in 10 days). Under sterile soil conditions, high soil moisture also enhanced the degradation of gliotoxin but level of degradation was less compared to unsterile conditions. Thus, gliotoxin stability is influenced mainly by the soil wetness, soil microbial community and pH conditions.

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