In the case arrestors with integrated inductances for
decoupling, the signal attenuated high transfer
frequencies. these systems, two further data cables be-
sides earth are protected.g. Depending the decoupling,
resistance increases the measuring circuits can oc-
cur with types FRD and FRD2.
Basic protection circuit measuring circuit
Use lightning barriers measuring circuits
Before lightning barriers are used measuring cir-
cuits, must first confirmed whether resistance
increase permitted. FLD/FLD2 an-
d/or MDP devices should therefore used this
case.
Ground-referenced systems are signal circuits that
have common reference potential with other signal
circuits. Therefore, when used measuring cir-
cuits with high transfer frequencies, lightning barriers
with resistive decoupling elements are the preferred
solution.Circuit diagram lightning barrier FRD/FLD
Circuit diagram lightning barrier FRD2/FLD2
Type series FRD/FLD
Type FRD, FLD and MDP lightning barriers are de-
signed for use so-called floating (asymmetrical, po-
tential-free) two-core systems. These are systems
whose signal circuits have common reference po-
tential with other signal circuits, e. The decision use FRD
(with resistive decoupling) FLD (with inductive de-
coupling) depends the system protected. current
loops.
Type series FRD2/FLD2
Type FRD2 and FLD2 are intended for use ground-
referenced (symmetrical, potential-referenced) single-
wire systems.
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Chapter The internal lightning protection system
. These devices can universally applied. The maximum operating current should also be
verified ensure that the dissipated energy does not
cause thermal destruction the decoupling elements. This can result er-
rors with current loop measurements
