Measurement Setup; General - Omicron CT SB2 User Manual

4

Measurement setup

4.1

General

When connecting the CT to the CT SB2 switch box, please also observe the wiring hints given in the
CT Analyzer User Manual.
Always connect only one CT to CT SB2. Disconnect and remove unused cabling from CT SB2 and the
CT after testing.
Using the CT SB2 switch box, CT testing, burden measurement and primary winding resistance
measurement can be performed separately (i.e., using separate test procedures) or together in one test
sequence. Figure 4-2 and Figure 4-3 show the basic wiring required for CT testing. To measure the
burden and the primary winding resistance together with the CT test, the additional wiring shown in
Figure 4-4 and Figure 4-5 is necessary (Advanced MR Test mode only).
The advantage of using CT SB2 for single-ratio CT testing is the option to include burden and/or primary
winding resistance measurement to the test without any need for wiring changes during the test
procedure. If you do not want to perform burden or primary winding resistance measurement, you should
preferably use the normal single-ratio test modes of CT Analyzer without using CT SB2.
If you do not use the CT SB2 switch box for CT testing with CT Analyzer, disconnect all cabling
to CT SB2 from CT Analyzer (incl. the data connection cable connected to the remote control
interface of CT Analyzer).
WARNING
Death or severe injury caused by high voltage or current possible
Accidentally mixing up primary and secondary windings can cause life-threatening
voltages and/or destroy the connected CT, the CT SB2 switch box, or the CT Analyzer
test set.
► When measuring the ratio of current transformers, make sure that the test voltage is
connected to the corresponding secondary winding, and the primary winding is
connected to the according measurement input.
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.
► When testing multi-core CTs, make sure that no other windings of the CT are open.
Leave the secondary windings of the other (non-measured) cores connected, or short-
circuit them if the windings are open.
► Always connect all secondary taps/windings to the CT SB2 switch box in order to
guarantee safety during testing.
OMICRON
Measurement setup
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