Tettex TTR 2795, Operating Instructions Manual

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14 Connection and Setup
4.5 Single Phase Transformers
To connect to a single-phase transformer using the standard three-phase cable set, the cables must be connected to
the unit, using the extension leads if required. Ensure that the connectors are locked fully home. The connections
should be made as follows:
Transformer Terminal TTR Connection
ANSI, IEEE IEC, VDE AS (Australian) “H” (Green Plugs) “X” (White plugs)
H1 U A Brown Lead
H0 N N Blue Lead
X1 u a Brown Lead
X0 n n Blue Lead
Figure 7 : Connecting To Single Phase Transformer
If an autotransformer is being tested, then the H0 and X0 terminals are common. The plugs supplied with the test
cables are stacking types. The Blue “X” cable (White plug) should be stacked onto the Blue “H” cable (Green Plug).
When connecting to an autotransformer, great care should be taken to ensure that the “H”
connection is connected to the top of the winding, especially if the transformer has an over-
wind on it. Failure to do this may result in damage to the transformer and the instrument.
4.6 Three Phase Transformers
Connecting to three phase transformers depends on whether the transformer is equipped with neutral connections on
primary or secondary.
If there is no primary neutral
connection , the H0 lead (Blue lead,
Green Plug) is left unconnected. It must
be placed in such a way that it is isolated
from earth and from any other connection,
and that there is no possibility of it being
touched by any personnel during the test.