Idiomas disponibles
Idiomas disponibles
4.3. Tips for Making Precise Ratio Measurements
The TR8703 is designed for step-down transformers. It sources low
voltage on the primary. It starts with a fraction of the final source voltage
and checks the secondary voltage.
If it exceeds the primary by a pre-determined value, the safety feature
stops the measurement. The recommended procedure is to reverse the
leads in these circumstances so that the primary of the transformer is
connected to the H cables and the secondary of the transformer is
connected to the X cables.
CAUTION: It is important to check that the H cables are connected
to the primary side and the X cables are connected to the
secondary side of the transformer before the test begins.
Always verify the integrity of the cable connections and reposition the
clips as necessary for robust and low-resistance connections. Inspect
the transformer terminals for dielectric coatings, fungus, dirt or
corrosion
Running a continuity test before the ratio test will provide a useful way
to check windings and connections
When testing polyphase transformers, keep in mind that in some
cases, the measured ratios must be multiplied or divided by √3. Refer
to § 6 for polyphase connection diagrams and associated ratio
equations
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