Operation
44
EDS309x_D00012_03_M_XXEN/11.2014
12. Start the insulation fault location from the main distribution area of the IT system. Place the
measuring clamp around all system conductors, but not the PE conductor. During each meas-
urement wait one test cycle (approx. 30 seconds). A flashing alarm LED on the EDS195P signals
an insulation fault after (from the point of view of the locating current injector) the measuring
clamp. It recommended to have the buzzer activated during the search.
13. Now measure along the cable using the EDS195P until the fault is found. During this process
move into sub-distribution systems using a star-shaped approach. The location of the fault is
found when the locating current in the measuring clamp generated by the PGH18… exceeds
as a minimum the response value set on EDS195P.
Possible error messages
Self test error:
– Incorrect current transformer type set
– EDS195P hardware faulty
– Clamp moved while the indication ">>>Self test<<<" was displayed
– An interfering residual current is flowing through the clamp
– There is a PGH locating pulse acting on the clamp
No CT connected:
Measuring clamp or measuring current transformer not connected or faulty.
Error I
ΔL
(can only be indicated while a measurement is in progress):
– Low frequency interference, measurement not possible
– EDS195P hardware faulty
I
Δn
>10 A / >1 A:
There is a residual current > 10 A or >1 A flowing through the measuring clamp. In this case it is
not possible to locate the insulation fault on the related outgoing circuit. Residual currents of
this magnitude in an IT system can be caused by large system leakage capacitances or multiple
insulation faults. It is therefore possible that there is an insulation fault on this outgoing circuit
also with this alarm message.
At operating currents < 10 A a measurement can also be made by placing the
clamp around only one conductor. At currents > 10 A it may no longer be possi-
ble to open the measuring clamp. This risk is particularly apparent in DC systems.
If this effect occurs, under no circumstances apply force; this action would irrep-
arably damage the measuring clamp. Instead the related system must be shut
down. It will then be possible to open the measuring clamp without the need to
apply force.
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