R&S ENV4200
Preparing for Use
User Manual 1107.2470.12 - 03
E-18
Make sure that the RF reference ground is not impacted by disturbance voltages (e.g.
from an industrial network) when the protective earth conductor is connected to the
protective earth. If this is the case, the protective earth must be connected via a PE
choke. With the choke, make sure that no voltages constituting a shock hazard are
applied to the housing.
4.5.1 Avoiding Grounding Loops
To avoid grounding loops, the V-network should be grounded only once in the test
setup, if possible. An example of using a PE choke was already given above (ensuring
that the RF reference ground is not impacted by disturbance voltages from an
industrial network).
shows an arrangement with several artificial mains networks
(AMN), source: CISPR 16-2-1:2014 (Edition 3).
Fig. 6
Arrangement of PE chokes to avoid grounding loops
PE chokes for currents up to about 30 A are common. In case of higher currents, you
can make them yourself by using ferrite toroidal cores. The following rule applies: In
case of a short circuit, the voltage drop at the PE choke must not exceed 4 V.
RF
referen
ce
ground