Omicron CT Analyzer Getting Started page 17

3.3 Connection for a CT test
This section shows the basic wiring of the CT Analyzer for a CT test.
Observe the general safety rules in section 3.1 on page 14 and the safety instructions given in chapter
1 "Safety instructions" on page 4. Observe the hints and instructions for improving the quality of the
measurement results given in the CT Analyzer User Manual.
WARNING
Death or severe injury caused by high voltage or current possible
Feeding test voltage to a CT can cause life-threatening voltages on other taps and/or
cores of the CT.
► Do not touch other taps or windings of the CT during the test.
► Make sure that no other windings of the CT are open.
NOTICE
Falsification of measurement results possible
► Always connect the grounded terminal on the secondary side of the CT to the black sockets of input
"Sec" and the "Output" of the CT Analyzer. Connecting the red sockets of the CT Analyzer to PE
can result in incorrect measurement and/or cause an automatic abortion of the measurement with
an error message.
► If it is necessary to use clamps for the connection of the measurement leads to the secondary side
of the test object, always use the 4-wire connection technique as described in the CT Analyzer User
Manual in order to avoid measurement errors.
For a CT test, connect the CT Analyzer as shown in Figure 3-1:
1. Make sure that the primary side of the CT is connected to PE on one side and open on the other side.
NOTICE
Falsification of measurement results possible
It is absolutely important to avoid coupling of interferences into the primary circuit during
measurement.
► Connect the side of the primary circuit that is able to receive more interferences to PE (e.g. the
side with the longer line length). The ungrounded side should be the side that receives less
interferences (refer to Figure 3-1).
2. Disconnect all secondary windings of the CT core under test in order to remove any load from this
core. Every kind of load remaining on the secondary side of a CT core during measurement will lead
to incorrect measurement results or error messages.
If the CT under test is a multi-core CT, leave the secondary windings of the other (non-measured)
cores connected, or short-circuit them if the windings are open.
3. Connect the black socket of CT Analyzer input "Prim" to the grounded side of the CT's primary circuit
and the red socket of this input to the open (ungrounded) side.
4. Connect the black "Output" socket and the black socket of input "Sec" of the CT Analyzer to that
terminal on the secondary side of the CT that is connected to PE.
OMICRON
Setup and connection
17