3.4 System Details
3.4.1 System Check:
The instrument is Line operated. It is designed to be used with voltage power sources (mains
power) 110/240 VAC 50/60Hz. The system performs a self-check each time that it is
powered on. The User should always visually inspect all connectors, cables and devices to
be measured to avoid any safety issues.
3.4.2 Transformer Turns Ratio Testing:
A Transformer Turns Ratio Meter does exactly as its name implies; it is used primarily for
checking the ratio of Turns of wires of the primary side and the secondary side of a
transformer. The Turns Ratio test set does not tell exactly how many turns of wire are in the
primary and secondary coils. But rather, it measures and displays the
Ratio
of (or
comparison of) the number turns in the primary coil to the number of turns in the secondary
coil.
This is an extremely useful device to check for shorted turns and incorrect settings of tap
changers. The TR-MARK III has an additional feature of allowing the operator to measure the
actual phase angle and vector relationship of the windings.
It is important to understand that the Nameplate Ratio on most transformers is the Voltage
ratio (Voltage in: Voltage out) and this Ratio is determined, basically, by the number of turns
of wire on the Primary (High side), the number of turns of wire on the Secondary (Low Side).
On a single phase Transformer the Turns Ratio is the same as the Voltage Ratio.
A Single Phase transformer:
For example: The High Side Winding may contain 940 Turns: Low Side Winding 440 Turns.
Therefore:
With three (3) Phase Transformers of different configurations, Turns Ratio and Voltage Ratio
can be, and usually are different.
90100-2.20 Instruction Manual TR-MARK III 250V
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