TBS
Blitzschutz-Leitfaden
2018
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2020/01/10
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2020/01/10
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134
Chapter The external lightning protection system
.13.2
µs the applied impulse voltage 1. The value limited downward direction that
no partial lightning current can flow into the building. an
induced voltage only present insulated con-
ductor when lightning strikes, resistive field control
can used avoid floating discharges. For this, the test-
ing arrangement used basis, which also
used for the high-voltage testing according IEC TS
62561-8 and represents the worst-case scenario.2.
The voltage load lightning strike impulse
voltage. As
an example, the left image shows the field diagram of
this arrangement with applied impulse voltage of
1,000 the area the equipotential bonding ter-
minal. This allows optimisation the resistance
value the resistive field controller.2 the applied impulse voltage 1.2/50 below
the earthed fastening clamp. potential 1,000 is
applied the internal conductor. Both diagrams show how the nu-
merical, time-discreet field calculation can used to
optimise the resistive field control that the current
in the field control layer can kept small pos-
sible, whilst still avoiding the formation floating dis-
charges.
Field diagram insulated conductor the first equi-
potential bonding terminal during type test time =
1.
Current density vectors resistive field control and po-
tential density insulated conductor time 1.2/50.2. Using the numerical field calculation, the res-
istive field controller can calculated time-dis-
creet manner for the entire course the impulse
voltage.
In upward direction, the value given the re-
quirement for effective field control.
Here, equipotential lines and the vertical electrical field
lines can seen. The lower
the resistance designed be, the more effective it
is.4 Potential control
For safe operation insulated conductor, meas-
ures avoid floating discharges are necessary. The right-hand image uses cross-sec-
tion diagram show the current density vectors and
equipotential areas. Within the external conductive layer
and the resistive field control layer, the current lines
can seen, which are significant for avoiding floating
discharges
