3.
Data cable with indirect earth one side
One way avoiding equalising currents earthing
the shield indirectly one end.
Device 1
Device 2
Data cable
Direct connection earth
Indirect connection earth
Gas-discharge table
Equipotential busbar
Earthing cable
Indirect earth one side
TBS
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Chapter The internal lightning protection system
. The connection the other
end has low resistance, leads directly the
equipotential bonding, the lightning current or
surge voltage can arrested both ends. TN-C net-
works, severe interference can also occur the data
cable. This happens when the earth res-
istance different different earthing systems, thus
creating potential difference. the two systems are
connected via the shield, the equalising currents at-
tempt eliminate the potential difference.5 Transmission characteristics
Due their sensitive signal levels, data cables are
particularly susceptible interference. the current too great and the shield can-
not withstand it, cable fires can occur.3. This can lead
to connection errors complete interruption the
signal. Because the gas-discharge
protector has resistance several gigaohms, there
is direct connection between the individual earthing
systems.
If the shield impacted lightning, the gas-dis-
charge protector ignites. The high impedance one end prevents
equalising currents from flowing.1. The larger
the difference potential, the greater the equalising
currents. This en-
sures that the shield not exposed the full current
at just one end.
Equalising currents are, however, still able flow
through the shield. The integ-
ration surge protection devices also counts an
intervention the cable. case interventions the cable, for ex-
ample the integration connection sockets, plugs
and adapters, even the bending radius too
small, can safely assumed that signal losses will
occur.TBS
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2018
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en
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2020/01/10
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2020/01/10
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Cable shields minimise interference conducting
away the currents from the parasitic capacitances. This done con-
necting the shield the equipotential bonding via a
gas-discharge protector. the losses are too great, certain transmission
standards will longer complied with
