Electromagnetic Radiation Level for 132kV line

FS MI017

Electromagnetic Radiation Detector 

To misure eletric field at your home.

 

Power lines: specific voltages

Whole list all possible overhead voltages

 

132 kV overhead lines: magnetic fields

132 kV overhead lines are usually carried on lattice steel pylons, but smaller than used for 275 kV and 400 kV lines.  Sometimes they are carried on wood poles.

The maximum field is produced by the largest design of line – the L7 – when the ground clearance is the minimum allowed – 7.0 m – and the loads are the highest allowed – 1.4 kA in each circuit.  The field also depends on the phasing. 132 kV lines usually have Untransposed (U) phasing.

graph showing maximum fields

Typical fields are lower than the maximum field because the clearance is usually higher and the loads are usually lower.  The three curves shown here are for typical loads, the normal U phasing, and three different line designs: L7 (the highest), a smaller pylon design, the L132, and a wood-pole design (the lowest field).

graph showing typical fields

 

Magnetic field in µT at distance from centreline

Type of lines

maximum under line

10 m

25 m

50 m

100 m

largest lines

L7

twin bundles

0.305 m

lynx

maximum

clearance 7 m
phasing U
load 1.4/1.4 kA

30.445

20.532

5.553

1.528

0.392

   

typical

clearance 10 m
phasing U
load 0.13/0.13

1.848

1.359

0.468

0.138

0.036

smaller lines

L132

single conductors

0.4 sq in

maximum

clearance 7 m
phasing U
load 1.2/1.2 kA

24.585

17.217

4.587

1.247

0.318

   

typical

clearance 10 m
phasing U
load 0.13/0.13 kA

1.731

1.317

0.451

0.132

0.034

smallest wood-pole design

trident

150 m span

single conductors

lynx

maximum

clearance 7 m
single circuit
load 0.7 kA

12.347

3.633

0.738

0.192

0.048

   

typical

clearance 10 m
single circuit
load 0.1 kA

1.764

0.385

0.099

0.027

0.007

 

 

132 kV overhead lines: electric fields

132 kV overhead lines are usually carried on lattice steel pylons, but smaller than used for 275 kV and 400 kV lines.  Sometimes they are carried on wood poles.

The maximum field is produced by the largest design of line – the L7 – when the ground clearance is the minimum allowed – 7.0 m.  The field also depends on the phasing. 132 kV lines usually have Untransposed (U) phasing.

graph showing maximum field

Typical fields are lower than the maximum field because the clearance is usually higher.  The three curves shown here are for the normal U phasing, and three different line designs: L7 (the highest), a smaller pylon design, the L132, and a wood-pole design (the lowest field).

graph showing typical field

 

Electric field values are misured in Volt / meter at distance from centreline

Type of lines

maximum under line

10 m

25 m

50 m

100 m

largest lines

L7

twin bundles

0.305 m

lynx

maximum

clearance 7 m
phasing U

3615

913

182

81

23

   

typical

clearance 10 m
phasing U

2372

890

103

72

23

smaller lines

L132

single conductors

0.4 sq in

maximum

clearance 7 m
phasing U

2628

697

154

66

19

   

typical

clearance 10 m
phasing U

1780

689

86

59

18

smallest wood-pole design

trident

150 m span

single conductors

lynx

maximum

clearance 7 m
single circuit

1174

588

73

11

2

   

typical

clearance 10 m
single circuit

583

458

89

15

3

 

Summaries of fields from all power lines

graph comparing typical magnetic fields

graph comparing typical electric fields

 

Exposure limits in Italy

Italian flagThe national Italian EMF limits currently in force were set by Decree of the Prime Minister in August 2003, replacing a previous decree of 1992.

For the general public, the limits are:

  • Electric fields: 5 kV/m
  • Magnetic fields: 100 µT

In addition, for magnetic fields, and applying to overhead power lines only, there are two further values:

  • The attention value: 10 µT. Applies where exposure is for more than 4 hours per day.
  • The quality target: 3 µT. Applies to new lines and to new homes only.

(both these values are limits on the daily averages, values at times during the day can be higher)

Three Italian Regions – Veneto, Emilia-Romagna and Toscana – set exposure limits in 1999 and 2000 for power lines at 0.2 µT for new installations near nurseries, schools, hospitals, houses and places where people spend more than four hours per day. Veneto also has a similar limit of 0.5 kV/m. These regional laws remain in force, but the national Decree prevents any other Regions doing likewise.

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One thought on “Electromagnetic Radiation Level for 132kV line

  1. Ad un’altezza di circa 2 metri (io con il braccio alzato in alto),
    sotto il traliccio alle 18.00 circa c’erano 1500 V/m
    Questa sera, stesse condizioni iniziali, invece arrivava appena a 500 V/m

    il traliccio è alto 9 metri.
    Le misure standard sono effettuate ad 1 metro dal suolo e tralicci L7 (alti 7 metri), quindi nel mio caso ho 1 metro differenza (9 metri – 2 metri invece di 7 metri – 1 metri )
    Il segnale va a 0 ad una distanza di circa 20 metri rispetto a quello riportato dai grafici (ma ho sempre 1 metro di vantaggio)

    Interessanti comunque sono i limiti presenti in Veneto:
    power lines at 0.2 µT for new installations + limit of 0.5 kV/m

    mentre per Italia in generale abbiamo:
    •Electric fields: 5 kV/m
    •Magnetic fields: 100 µT

    •The attention value: 10 µT. Applies where exposure is for more than 4 hours per day.
    •The quality target: 3 µT. Applies to new lines and to new homes only.

    In pratica è il campo magnetico, misurato in Tesla, che fa casino ed è + pericoloso.

    Dai grafici si ricava che ad una distanza di circa 25 metri abbiamo:
    – Campo Elettrico tipico = 103 V/m
    – Campo Magnetico tipico = 0.468 µT

    e siamo abbondantemente al di sotto dei valori minimi.

    I livelli da considerare “pericolosi” sono riportati qui:

    There are established biological effects for acute high level exposure to magnetic fields well above 100 µT (1000 mG). In a residential setting, there is “limited evidence of carcinogenicity in humans and less than sufficient evidence for carcinogenicity in experimental animals”, in particular, childhood leukaemia, associated with average exposure to residential power-frequency magnetic field above 0.3 µT (3 mG) to 0.4 µT (4 mG). These levels exceed average residential power-frequency magnetic fields in homes which are about 0.07 µT (0.7 mG) in Europe and 0.11 µT (1.1 mG) in North America
    https://en.wikipedia.org/​wiki/​Power_lines#Health_concerns

    Tanto per darti un riferimento: il misuratore segnava 1450 V/m circa vicino al salvavita da 25A all’ingresso di casa, però lo devi appoggiare al muro. Ad una distanza di 10 cm già riportava un valore di 400 V/m
    Il riassunto è che il campo elettrico di una linea ad alta tensione di 1500 V/m corrisponde ad un campo elettrico di casa con circa 10-15A

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