Haefely WA 2293 User manual

Designed by
WA 2293
Automatic Transformer
Winding Analyser
Leaflet

The 2293 is an automatic winding analyser, optimized for three
phase power and distribution transformer measurements.
It uniquely combines winding resistance measurement, turns
ratio, dynamic resistance measurement, core demagnetization,
transformer type detection, magnetic balance, short circuit
impedance and heat run test (temperature rise and cooling
curve) in the fastest, single instrument solution in the market.
A simple “one-time-connection” system drastically reduces
measuring time: once connected all tests can be performed in
a row without any reconnection.
The built-in, simultaneous winding magnetization method
guarantees fast and reliable resistance measurements. Stable
measurements are reached even on large power transformers
with delta windings on the low voltage side. A progressive
method for measuring transformer turns ratio, guarantees
results closer to the nominal ratio even in large power
transformers with tertiary windings.
MULTI-PURPOSE AUTOMATIC POWER TRANSFORMER WINDING ANALYSER
Multi-purpose winding analyser - all in one solution.
Simple “one-time connection“ system.
Unique simultaneous winding magnetization method for
winding resistance measurements.
Touchscreen interface with full graphical test visualization.
Dynamic resistance for tap charger diagnosis, automatic tap
changer control device.
Advanced procedure for turns ratio and phase displacement
measurement.
Demagnetization function.
Automatic magnetic balance test.
Short circuit impedance at reduced current.
One device for transformer winding resistance, turns ratio,
arbitrary phase, vector group check, demagnetization,
dynamic resistance, short circuit impedance, magnetic
balance and heat run test (heat rise and cooling curve).
Once connected, can perform all tests in all phases on both
windings.
More compact and lightweight solution in comparison to
traditional equipment with up to 100A test current.
Easy operation.
Fully automated twinding resistance and tap changer test.
Measurement also on non-regular phase displacements
(arbitrary phase shifted transformers).
Transformer is returned to a demagnetized status after
winding resistance measurement or before putting the
transformer into service.
Magnetic core fault detection.
Mechanical damage detection.
FEATURES ADVANTAGES
The 2293 is a valuable tool for factory test, acceptance test
and regular maintenance on:
■Power and distribution transformers
■All types of HV windings
APPLICATIONS
Dynamic resistance measurement on tap changer, performs an
efficient and reliable check of the transformer tap changer.
The demagnetization function eliminates the magnetic
remanence, which can cause faulty measurements, high inrush
currents and incorrect operation of protective relays.
Short circuit impedance test, at reduced current, helps to
locate mechanical damages. In addition, the magnetic balance
test can detect faults in the transformer magnetic core.
Personnel safety is guaranteed by an emergency button, as
well as a state-of-the-art active discharge circuit, and a caution
indicator that continues to operate even without line power.
An optional interlock connector can be ordered.
32A and 18 kg multi-purpose winding analyser. Once connected, all tests are done without reconnection.
2 3
Powerful & Compact with “One-Time Connection“

TURNS RATIO
Transformer turns ratio validates the
transformer design, or detects incorrect
number of turns. In the field, changes in the
turns ratio could indicate shorted turns, core
related faults or mechanical damages.
HEAT RUN TEST - HEAT RISE
The 2293 monitors the transformer
temperature during the heat rise and includes
pre-configured tests according to IEC and
ANSI standards, informing when stabilization
has been reached.
HEAT RUN TEST - COOLING CURVE
During the cooling curve, the 2293 measures
HV and LV side resistances simultaneously and
accurately. Efficient and accurate acquisition
of the data points allows easy drawing of the
cooling curve.
DEMAGNETIZATION
A magnetized core can generate large over
currents when connected to the grid (inrush
current), or generates wrong results during
other measurements (e.g., frequency response
analysis).
MAGNETIC BALANCE
Magnetic balance test is performed to detect
faults in the magnetic core. The test looks for
changes in the reluctance of the magnetic
circuit caused by defects in the magnetic core
structure, shifting or shape changes in the
windings or inter-turn insulation fault.
TRANSFORMER CONNECTION
Transformer connection finder is used in
repairingshops,orduringroutinemaintenance,
to measure transformers with non available or
deleted nameplates.
WINDING RESISTANCE
Transformer winding resistance is a routine
testforallmanufacturedpowertransformers.
Inthefield,changesinthewinding resistance
with time, can indicate looseness or
overheating.
ARBITRARY PHASE SHIFT
Special transformers, like phase shifting or
arc furnace, which don’t follow the standard
30° phase steps can be easily measured.
DYNAMIC RESISTANCE ON TAP
CHANGER
Dynamic resistance measurement is a
reliable check of the transformer tap
changer. Discontinuities or deviations
between different taps are signs of tap
changer fault.
SHORT CIRCUIT IMPEDANCE
Changes in the short circuit impedance
along transformer life, is normally an
indication of mechanical damage.
WA 2293 - FLEXIBLE WA 2293 - FACTORY OPTIMIZED
WA 2293 - ON-SITE OPTIMIZED
The available software add-ons, allow adding features while the device is live without the need of hardware modifications or re-
calibrations. Just acquire the additional software add-on and the new feature will be automatically included.
The add-on achitecture, allows device optimization for factory use, on-site use, or both.
The WA 2293 is the perfect device for factory test according to
IEC 60076. Its accuracy and reliability make it a must have for
transformer tests.
The 2293 add-ons concept allows to configure the device with
the most important measurements to perform routine test on
both distribution and power transformers.
Time-based or status-based maintenance requires reliable
devices with trustable measurement results to decide the
transformer status. Using the 2293 add-ons feature, the device
can be tuned to be used on this particular field. Being lightweight
and easy to connect, makes it the perfect partner to perform
on-site measurements.
Winding Resistance
Demagnetization
Winding Resistance
Heat Run - Cooling Curve
Tap Changer - Dynamic Resist
Turns Ratio
Short Circuit Impedance
Transformer Connection
Magnetic Balance
Heat Run - Heat Rise
Turns Ratio
Arbitrary Phase Shift
Standard
Optional
4 5

ALL IN ONE
Printer
A simple test report can be printed with the built-in thermal
printer.
Data Handling
The 2293 allows easy data handling. Results can be saved on
a USB memory stick or downloaded to a computer using the
embedded FTP server.
Remote Control
Remote control is performed through the Ethernet interface
tointegratethedeviceinanautomatedproductionplatform.
Safety Switch
The safety switch can be turned off at any point of time to
disconnect the device, thereby guarenteeing complete
safety.
Quick Connection System
The twin-lock connectors and the one-time connection
system help to reduce connecting time drastically.
TemperatureMeasurement
Temperature probes inputs (6 included, up to 30 with the
2293/TEMPEXT) to monitor the test object temperature
during resistance measurement or heat run test.
Tap Changer Control
Motorized tap changers can be remotely operated by the
device to automate measurements.
Touch Screen
Self-guided graphical interface and touch-panel makes
device user-friendly.
6 7

The simultaneous winding magnetisation method (patented)
together with the integrated DC power-supply guarantees fast
and reliable winding resistance measurements. The 7” touch
screen full graphical interface guides the operator through the
single test procedures.
Independent currents can be selected for each winding, which
guarantees reliable results even in transformers with large
differences between windings.
WINDING RESISTANCE
With one optional temperature probe (available for liquids and
magnetic), results can be automatically referenced to any target
temperature (for example 75°).
The AC power supply integrated in the 2293 allows full
automatic measurement of turns and voltage ratio, ratio
deviation, phase displacement and excitation current of
transformers.
Arbitrary phase shifts or those that do not follow the 30°
phase steps between the primary and secondary winding
are common in special transformers like phase shifting,
rectifier / furnace and traction transformers.
With the optional arbitrary phase shift software key (2293/
SKAP), the 2293 can measure turns and voltage ratio, phase
displacement and excitation current of these special type
transformers.
The specially developed algorithmic included in
compensated mode reduces the influence of leakage flux
while using low voltage, giving results much closer to the
nominal ratio.
The included type detection feature works as a nameplate
guesser. It helps the user to determine the correct
transformer configuration by showing the possible types
and eliminating the wrong vector groups during the
automatic detection process.
TURNS RATIO
ARBITRARY PHASE SHIFT
VECTOR GROUP DETECTION
With Simultaneous Winding
Magnetization Test a complete
transformer in a fraction of time!
8 9

U
(A)
V
(B)
W
(C)
Voltage to U (A) 100% 66% 33%
Voltage to V (B) 50% 100% 50%
Voltage to W (C) 33% 66% 100%
The main functionof theon loadtap changer isto switchbetween
transformer taps without interrupting the current. The 2293
registers the current while tap changer is operated and records
the values at a defined sample rate.
Discontinuities or deviations between different taps are a sign
of tap changer fault.
TAP CHANGER - DYNAMIC RESISTANCE
The tap changer test with the 2293 is done automatically and
without reconnection. In addition, the tap changer control
accessory allows a complete automatic sequence without
human intervention.
Calculation of the main curve parameters like time to rise, time
to fall or delta, for failure detection, is automatically done.
Magnetic balance test is performed to detect faults in the
magnetic core. The test looks for changes in the reluctance
of the magnetic circuit caused by defects in the magnetic
core structure, shifting or shape changes in the windings or
inter turn insulation fault.
The test is performed on three phase transformers by
applying a voltage on one of the phases and measures the
voltage on the other two. The induced voltage will depend
on the limb position into the core as the following table.
The 2293 performs the magnetic balance test automatically
and without any reconnection. Test results are shown
graphically for a better understanding.
Imbalances will be graphically noted including the involved
phases.
Short circuit impedance is a routine test done to all
transformers after manufacture and specified in the
transformer nameplate.
Changes in the short circuit impedance along transformer
life is normally an indication of mechanical damages.
The 2293 automatically performs a short circuit impedance
test at reduced voltage on power and distribution
transformers and calculates the three phase equivalent
short circuit impedance for comparison with previous test or
with nameplate values.
After a power or distribution transformer is disconnected
from the power grid or when a DC current is applied to it, for
example during a routine winding resistance measurement,
the transformer core is likely to have some remnant
magnetism. This remnant magnetism will generate high
over currents when the transformer is reconnected to the
grid, and this is commonly known as transformer inrush
current.
In addition, magnetic remnant has an adverse effect on
other measurements like FRA or TTR.
The 2293 includes a fully automatic demagnetisation feature
which eliminates the magnetic remnant. Select the winding
where demagnetisation needs to be performed and press
start. The unit visualizes the whole demagnetisation cycle
and performs the correct core demagnetisation in seconds.
MAGNETIC BALANCE TEST SHORT CIRCUIT IMPEDANCE
DEMAGNETISATION FUNCTION
10 11

Heat run test on transformers consist of two steps:
■Heat Rise: The transformer runs at nominal losses and
transformer temperature rises.
■Cooling Curve: The transformer is disconnected and winding
resistance is measured.
The 2293 performs the measurements on both steps. It
monitors the transformer temperature during the heat rise and
measures HV and LV side resistances simultaneously during
the cooling curve.
HEAT RUN TEST
For the heat rise, connection of the temperature sensors
could not be easier. The included 6 temperature inputs can
be easily extended up to 30 by using the optional
temperature extension box (2293/TEMP). The available
magnetic and liquids temperature probes (2293/TEMP2,
2293/TEMP1) are easily connected to the transformer.
Probe configuration is done graphically (oil, radiator top,
radiator bottom, ambient…).
In addition, pre-configured tests according to ANSI and
IEC standards are included, calculating the transformer
temperature in real time and informing when stabilization
is reached.
For the cooling curve, the 2293 can measure HV and LV
side resistances simultaneously and accurately. It provides
efficient and accurate acquisition of the required data
points to allow the user to draw the necessary cooling
curve. Results can be easily exported to CSV files to
calculate the winding temperature at switching off time.
HEAT RISE COOLING CURVE
12 13
Connect up to
30 temperature sensors
to the WA 2293
Pre-configures
test according to
ANSI & IEC

WA 2293
Ease of
Use
IEC
IEEE
Automatic
Report
Safety
Speed
Diagnosis
Approved
ENTIRE SOLUTIONS FOR TRANSFORMERS
Haefely offers a complete product line for transformer tests, both in the factory and on-site.
7
8
6
1
4
1
2
3
10
5
9a 9b
9a 9b
Turns Ratio Measurement
Range 1.0 … 100’000
Accuracy 0.05%
2293 BASIC SPECIFICATIONS
Complete technical specifications in the WA 2293 datasheet available at www.haefely.com
Resistance Measurement
Max. Measuring Current DC 32A (user selectable)
Max. Charging Voltage DC 100V
Range 0.1 μΩ … 300 kΩ
Accuracy 0.1% ± 0.5 µΩ
STANDARD PACKAGE
EXTENSIONS
WA 2293
3490068 Measuring Bridge (Portable and
rack mounted version)
WA 2293
Software Add-ons
3-phase transformer turns ratio measurement 2293/SKTTR
Arbitrary phase shift (2293/SKTTR needed) 2293/SKAP
Heat rise temperature measurement 2293/SKTR
Magnetic balance measurement 2293/SKMB
Tap changer dynamic resistance measurement 22937/SKTC
Short circuit impedance measurement 2293/SKSC
Extended Warranty
2 years WA 2293
3 years WA 2823
Including
■Winding resistance measurement
■Demagnetization measurement
■Heat run - Cooling curve measurement
■8 measuring cables of 10 m length equipped
with Kelvin probes
■Cable bag
■Test certificate
■Instruction manual
1
2
3
Measurement Cables & Clamps
Extension cable 10 m high voltage side
Extension cable 10 m low voltage side
2293/10HV
2293/10LV
Additional measuring cables (HV & LV, 8 cables), 3 m length 2293/MK3
Tap changer control cable, allows remote tap changer control from measuring
device and automate test sequences
2293/TAP
Extension clamps to increase the maximum openning distance of the standard
clamps
ExtClamp
Temperature Sensors
Temperature extension box to connect up to 8 additional temperature sensors
(max. 3 extension boxes per device)
2293/TEMPEXT
Temperature probe for liquids 2293/TEMP1
Temperature probe magnetic 2293/TEMP2
Laser infrared contactless thermo/hygrometer TEMP
Provisions
Interlock provision 2293/IT
ACCESSORIES
4
9a
5
6
7
8
9b
10
14 15
Winding Resistance
TTR Turns Ratio
Heat Run Test
Demagnetize
Cap & Tan (Diss. Factor)
Short Circuit Impedance
FRA Frequency Response
RVM Water Content
Excitation Current
WA 2293
MIDAS micro
2283
FRA 5311
RVM 5462a

This document has been drawn up with the utmost care. We cannot, however, guarantee that it is entirely complete, correct or up-to-date.
Subject to change without notice.
V2109
HIGH VOLTAGE
INSTRUMENT
EMC
HV
IN
EM
precision.
r
eliable.
EUROPE
HAEFELY AG
Birsstrasse 300
4052 Basel
Switzerland
 [phone]
 [e-mail]
 www.haefely.com
CHINA
HAEFELY AG Representative Office
8-1-602, Fortune Street, No. 67,
Chaoyang Road, Beijing 100025
China
 [phone]
 [e-mail]
 www.haefely.com
INDIA
HAEFELY India Service Office
C/o Pfiffner Instrument Transformers Pvt. Ltd.
176, 178/2 Sarul, Viholi
Nashik 422 010, India.
 [phone] (toll free)
 [e-mail]
 www.haefely.com
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