Introduction; History; General - Raytech TR–Mark III 250V Instruction Manual

3 Introduction

3.1 History

Raytech first developed the Transformer Turns Ratio Spy (TR-Spy) for high degree of
accuracy for the research and development of transformers. This technology was then
packaged into a portable test system for use by transformer manufacturers, rebuild shops,
and electrical maintenance crews. This first system had become the most widely respected
precision instrument for the ease of use, design, and operation. This first system was
developed with the assistance of transformer manufacturer's and utility test crews.
The second generation TR-Spy Mark II took this initial development and added many new
features to the system including a large memory base, external control for tap changer
testing and automatic voltage level detection test. The TR-Spy Mark II was a completely new
approach in technology and has become the standard for ratio testing.
Now, the third generation TR-MARK III 250V offers new features and increased accuracy to
make it a perfect system. A Color LCD with back lighting and touch screen increases
handling and user comfort. Two USB interfaces make it easy to store measurements on
external storage devices and transfer easily to a personal computer. And Test Reports; just
print them on the internal printer or from your computer.

3.2 General

Ease of use: This system is designed to be easily used and understood. Once the buttons
and few menus are learned, the system is very simple to understand and operate. This
intelligent system analyzes the configuration of a transformer and performs all required
measurements automatically for Voltage Ratio, Turns Ratio, Current, and Phase
Displacement. The system can operate a full 3 phase testing sequence with a single push
button operation. Connect the leads; select the transformer configuration & press GO to test.
Impressive Accuracy: The TR-Mark III 250V is a high precision, fully automatic,
microprocessor based, Single and Three Phase Transformer Turns Ratio Test system. This
system is designed for highly accurate readings on-site with laboratory precision. It is the
most accurate system available.
Unique Measuring Technique: This newly designed technique of measurement
incorporates a high precision dual-vector voltage meter for ratio readings and a rectification
resolution circuit for phase displacement (vector group). The phase displacement (vector
group) can be automatically detected and displayed without operator intervention.
Operation: The TR-Mark III 250V applies a small voltage on the HIGH winding side of the
transformer and measures back through the LOW side of the transformer. Analysis is made
and the system determines whether a test can be conducted. Then the system applies the
test voltage on the HIGH winding side of the transformer and measures the voltage back
through the LOW side of the transformer. This technique has been determined to be the
safest possible method of ratio testing. The results are reported on the easy to read touch-
screen display.
Advanced Protection: Upon powering on the system initializes itself with a self-calibrating,
circuit checking sequence. If any problems are detected during this initialization period, or
during operation, the operator is immediately notified. The system constantly monitors the
condition of the transformer under test. The TR-Mark III 250V can even recognize shorted
leads and will terminate the test without any damage to the test equipment. This works
especially well when test leads accidentally fall free from the transformer while under full
voltage measurement. Accidental interchanging of the test leads on the High and Low
voltage side is also detected and the measurement is safely halted.
Simple Maintenance: There is No maintenance required. There is No calibration procedure
(No potentiometers to turn). This is due to the utilization of high precision components in the
design.
Instruction Manual TR-Mark III 250V Version 1.10 Preliminary Page 5 of 57