Substation - 5-7 Ilia Mavromichali Street, Larnaca
On the of July 2010 at 09:45 pm electric and magnetic field measurements were performed for the Apartment 104, 5-7 Ilia Mavromichali Street in Larnaka and substation “Praxitelis”.
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Figure 1:Substation “Praxitelis Street” |
Figure 2: Apartment’s Bedroom No. 1 |
The substation is rated at a nominal power of 500 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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285 A |
211 A |
249 A |
Table 1: Measured load current
From the resultant load of all three phases as shown above we note that the load is only 35.76 % of the nominal load (500 KVA Transformer).
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 are represented below and compared to the ICNIRP limits. The highest magnetic field inside was observed in the apartment’s studying room, with a value 0.5 μT and a percentage of 0.5 % as compared to the ICNIRP General Public standard.
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Magnetic Field Measurements |
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Measurement point /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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Measurements inside the residence - Kitchen |
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Measurement point A |
-- |
-- |
0.20 |
0.20% |
-- |
-- |
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Measurements inside the residence - Office area |
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Measurement point B |
-- |
-- |
0.50 |
0.50% |
-- |
-- |
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Measurements inside the residence - Living room |
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Measurement point C |
-- |
-- |
0.05 |
0.05% |
-- |
-- |
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Measurements inside the residence - Childrens's bedroom |
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Measurement point D |
-- |
-- |
0.08 |
0.08% |
-- |
-- |
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Measurements inside the residence - Bedroom No 2 |
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Measurement point E |
-- |
-- |
0.10 |
0.10% |
-- |
-- |
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Measurements inside the residence - Toilet |
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Measurement point F |
-- |
-- |
0.30 |
0.30% |
-- |
-- |
Table 3: Magnetic Field Measurements inside area
Accordingly the highest magnetic field value outside was observed 0m away from the substation’s left side (3m from the starting point), with a value 2.885 μT and a percentage of 2.89 % as compared to the ICNIRP General Public standard.
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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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Substation - Front side |
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0m |
2.02 |
2.02% |
1.49 |
1.49% |
0.99 |
0.99% |
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1m |
0.72 |
0.72% |
0.55 |
0.55% |
0.39 |
0.39% |
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2m |
0.52 |
0.52% |
0.39 |
0.39% |
0.28 |
0.28% |
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Substaiton - Left side |
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0m |
2.89 |
2.89% |
1.33 |
1.33% |
0.95 |
0.95% |
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1m |
0.70 |
0.70% |
0.55 |
0.55% |
0.47 |
0.47% |
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2m |
0.36 |
0.36% |
0.29 |
0.29% |
0.29 |
0.29% |
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Substation - Right side |
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0m |
0.84 |
0.84% |
0.66 |
0.66% |
0.57 |
0.57% |
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1m |
0.45 |
0.45% |
0.33 |
0.33% |
0.30 |
0.30% |
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0.30 |
0.30% |
0.21 |
0.21% |
0.22 |
0.22% |
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Substation - Back side |
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0m |
2.09 |
2.09% |
1.91 |
1.91% |
1.66 |
1.66% |
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0.8m |
1.71 |
1.71% |
1.72 |
1.72% |
0.88 |
0.88% |
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1.6m |
0.86 |
0.86% |
0.74 |
0.74% |
0.83 |
0.83% |
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Above Substation - Apartment's veranda |
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0m |
1.14 |
1.14% |
0.64 |
0.64% |
0.38 |
0.38% |
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1m |
1.30 |
1.30% |
0.66 |
0.66$ |
0.41 |
0.41% |
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2m |
1.00 |
1.00% |
0.48 |
0.48% |
0.35 |
0.35% |
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3m |
0.70 |
0.70% |
0.42 |
0.42% |
0.27 |
0.27% |
Table 4: Magnetic Field Measurements outside area
Additionally, the highest electric field value outside was observed on the right side of the distribution transformer “Praxitelis”, with a value 0.742 V/m and a percentage of 0.01 % as compared to the ICNIRP General Public standard.
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Inside and outside Field Measurements |
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Measurement point /m |
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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Substation - Front side |
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Measurement point D |
-- |
-- |
-- |
-- |
0.60 |
0.01% |
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Substation - Left side |
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Measurement point E |
-- |
-- |
-- |
-- |
0.64 |
0.01% |
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Substation - Right side |
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Measurement point F |
-- |
-- |
-- |
-- |
0.74 |
0.01% |
Table 5: Electric Field Measurements inside and outside area