20
SN odvodniki prenapetosti
MV surge arresters
2SS15N splošno
2SS15N generally
• S
- pričakovana strmina prenapetostnega udara
strele
S
= 1550 kV/μs - leseni drogovi
S
= 800 kV/μs - ozemljene konzole
• S - anticipated steepness of over voltage lightning
strike
S = 1550 kV/μs - wooden poles
S = 800 kV/μs - grounding brackets
2. Izračun
Poenostavljena formula za izračun zaščitne razdalje:
V splošnem za zaščitno razdaljo velja, da naj bo odvodnik
priključen čim bliže ščiteni napravi.
Primer naročila:
Na naročilo napišemo kodo odvodnika tipa 2SS15N, ki
smo jo izbrali na osnovi izračuna za trajno obratovalno
napetost U
C
iz tabel:
SN odvodnik 2SS15N-R
koda: 21 48 13
Izbrani srednjenapetostni odvodnik prenapetosti
2SS15N-R ima trajno obratovalno napetosti U
c
= 24 kV in
nazivno napetost U
r
= 30 kV.
2. Calculation
Simplified formula for calculating the shielding distance:
Ingeneral for the shieldingdistance it is valid that the surge arrester
shouldbemountedas near as possible to the device it protects.
Ordering example:
We write the code of the surge arrester type 2SS15N which
we have chosen on base of calculation for continuous
operating voltage U
C
from tables:
MV surge arrester 2SS15N-R
code: 21 48 13
The chosen middle voltage surge arrester 2SS15N-R has the
continuous operating voltage U
c
= 24 kV and rated voltage
U
r
= 30 kV.
Nazivna napetost U
r
Rated voltage U
r
3,7 - 45 kV
Trajna obratovalna napetost U
C
Continuous operating voltage U
C
3 - 36 kV
Nazivni odvodni tok (8/20) I
n
Nominal discharge current (8/20) I
n
10 kA
Visok impulzni tok (4/10)
High impulse current (4/10)
100 kA
Tok dolgega vala
Long-duration current
250 A
Zdržni kratkostični tok
Short-circuit current
20 kA
Sposobnost energijske absorpcije (dolgi val)
Energy absorption capability (long duration)
2,8 kJ/kVU
c
Sposobnost energijske absorpcije (impulzni tok)
Energy absorption capability (impulse current)
4,8 kJ/kVU
c
Upogibni moment M
u
Cantilever strength M
u
250 Nm
Torzijski moment M
t
Torque M
t
80 Nm
Vertikalna sila F
v
Vertical load F
v
625 N
Električni podatki /
Electrical data
Razlaga naziva
2SS15N - R 21 48 13
Name interpretation
2SS15N - R
21 48 13
koda
oblika
tip
code
shape
type
1
3
4
5
6
9
7
8
2
