Substation - Substation Kyros Erotokritou, 62 Demetre Stavrou Street
On the 20th of July 2011 at 09:15 am electric and magnetic field measurements were performed for residence 62 Dimitri Stavrou Street in Nicosia and substation “Kyros Erotokritou Plots”.
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Figure 1: Substation Kyros Erotokritou |
The substation is rated at a nominal power of 315 KVA. At the time when the measurements were performed the substation load was recorded as:
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Red Phase |
Yellow Phase |
Blue Phase |
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25 A |
30 A |
40 A |
Table 1: Measured load current
From the resultant load of all three phases as shown above we note that the load is only 6.94 % of the nominal load (315 KVA Transformer).It must therefore be noted that during the summer or in periods of peak load this will directly affect and produce an increase to the electric and magnetic fields.
Limiting exposure values have been provided by the ICNIRP recommendations and are guidelines to many countries and organizations. The exposure limits at 50 Hz are tabulated in the following table according to the limits given by ICNIRP.
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Reference levels for Occupational exposure ICNIRP |
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Frequency |
Electric Field Strength, E (V/m) |
Magnetic Field Strength, H (A/m) |
Magnetic Flux Density, B (µT) |
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50 Hz |
10000 |
400 |
500 |
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Reference levels for General Public exposure ICNIRP |
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Frequency |
Electric Field Strength, E (V/m) |
Magnetic Field Strength, H (A/m) |
Magnetic Flux Density, B (µT) |
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50 Hz |
5000 |
80 |
100 |
Table 2: ICNIRP Exposure limits for Occupational and General Public exposure
The maximum obtained values from the investigation are represented below and compared to the ICNIRP specified limits of General Public and Occupational standards. The highest magnetic field measurement in the outside area was observed 1m away from the substation front side (0m away from the starting point) at a height of 0.30 m. The measured value at this point was 0.672 µT and a percentage of 0.672% as compared to the ICNIRP General Public standard.
Accordingly a detailed description of the maximum measured magnetic fields in the outside area is shown in the table below.
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Outside Field Measurements |
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Distance from Side /m |
Maximum Magnetic Field at Z Height /m - Percentage of ICNIRP General Public Standard /% |
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0.3m |
ICNIRP % |
1m |
ICNIRP % |
1.75m |
ICNIRP % |
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Outside the residence bedroom |
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Measurement point A |
-- |
-- |
0.07 |
0.07% |
-- |
-- |
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Inside the residence garden |
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Measurement point B |
-- |
-- |
0.06 |
0.06% |
-- |
-- |
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Substation front side |
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0 m from front side |
0.66 |
0.66% |
0.43 |
0.43% |
0.22 |
0.22% |
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1 m from front side |
0.67 |
0.67% |
0.23 |
0.23% |
0.18 |
0.18% |
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2 m from front side |
0.28 |
0.28% |
0.20 |
0.20% |
0.12 |
0.12% |
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Substation right side |
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0 m from front side |
0.35 |
0.35% |
0.26 |
0.26% |
0.19 |
0.19% |
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1 m from front side |
0.28 |
0.28% |
0.14 |
0.14% |
0.16 |
0.16% |
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2 m from front side |
0.33 |
0.33% |
0.17 |
0.17% |
0.17 |
0.17% |
Table 3: Magnetic Field Measurements - Outside area
The highest electric field measurement in the outside area was observed in the front side of the substation. The measured value at this point was 1.745 V/m and a percentage of 0.035% as compared to the ICNIRP General Public standard.
The electric field measurements in the outside area are shown in the following table
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Outside Field Measurements |
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Measurement Point |
Maximum Electric Field at Z Height /m - Percentage of ICNIRP General Public Standard /% |
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0.3m |
ICNIRP % |
1m |
ICNIRP % |
1.75m |
ICNIRP % |
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Residence Bedroom |
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Measurement Point C |
-- |
-- |
1.745 |
0.035% |
-- |
-- |
Table 4: Electric Field Measurements - Outside area