Page 1
WRM-40
winding resistance meterwinding resistance meter
Vanguard Instruments Company, Inc.
www.vanguard-instruments.com
Page 2
WRM-40
winding resistance meter
The WRM-40 is designed to accurately measure the winding resistance of
highly inductive power transformers. The unit’s dual resistance-reading input
channels can measure two winding resistances simultaneously, and four-wire
(Kelvin) connections provide high accuracy and require no lead compensation.
The WRM-40 provides stable resistance readings of very large transformers
by utilizing a 36Vdc power supply capable of outputting up to 40 Amperes.
The resistance reading of a 500MVA transformer can be achieved in 5 minutes
or less. The unit’s power supply is cooled by four heavy-duty fans designed for
continuous operation. For greater fl exibility in the fi eld, the WRM-40 comes
with a built-in 2.5-inch wide thermal printer used for printing test reports.
Since the WRM-40 can accurately measure resistances ranging from 1 microohm to 500 ohms,
it can also be used to measure EHV circuitbreaker contact resistance, motor winding resistance, or any low resistance. If the transformer
winding temperature is entered, the WRM-40
can calculate the equivalent resistance value of
the winding material (aluminum or copper) at
any standard reference temperature. Also, a special test mode can run a test for up to 45 minutes
while saving resistance readings at one-minute
intervals. In addition to measuring the resistance
value, the WRM-40 also checks the “make-before-break” tap switching sequences of voltage
regulators and load tap changers.
The WRM-40 can store test results in Flash EEPROM. Test results can be printed on the built-in
2.5-inch wide thermal printer or can be transferred to a PC via the RS-232C interface port.
The WRM-40 is furnished with three 50-foot
test cables. Each test cable lead is terminated
with a quick-disconnect test clip.
Built-in Safety Features
At the end of each test, the WRM-40 automatically dissipates the stored energy in the transformer. This discharge circuit will continue to
work even if the supply voltage is lost. For added
safety, the unit’s power supply is thermally protected from over-load damage.
Internal Test Record
Storage
The WRM-40 can store 63 test records (up to
48 readings per test record) in Flash EEPROM.
Test records can be retrieved and printed on the
built-in thermal printer or can be transferred to a
PC via the RS-232C interface port. A Windows®
-based application is provided with each WRM40 that can be used to retrieve test records from
the WRM-40 and can also be used to export records in Microsoft® Excel format.
User Interface
The WRM-40 features a back-lit LCD screen (20
characters by 4 lines) that is viewable in both
bright sunlight and low-light levels. A rugged,
alpha-numeric, membrane keypad is used to
control the unit.
Built-in Thermal Printer
The WRM-40 features a built-in 2.5" wide thermal printer that can be used to print test reports
in the fi eld.
outstanding features
• Auto discharge circuit for operator safety
• Auto current ranging from 10 mA to 40 A
• Digital resistance reading from 1 microohm to 500 ohms
• Stores 63 records (of 48 readings each)
• Built-in 2.5-inch wide thermal printer
2
Page 3
WRM-40 Controls & Indicators
Power Switch
Resistance Input Channel #1
RS-232C PC Interface
Back-lit LCD Screen
Current Output Connectors
2.5" Wide Thermal Printer
Rugged Membrane Keypad
Resistance Input Channel #2
Warning Indicators
Thermal Printer Output
WRM-40 specifi cations
type portable transformer winding resistance meter
physical specifi cations 25”W x 8K”H x 20”D, (63.5 cm x 21.6 cm x 50.0 cm); Weight: 44 lbs (20 kg)
input power 100 ¬ 120 Vac or 200 ¬ 240 Vac (factory pre-set), 50/60 Hz
resistance reading range 1 micro-ohm¬ 500 ohms
accuracy 1 ¬ 19,999 micro-ohms: ±0.5% reading, ±1 count;
20 ¬ 999 milli-ohms: ±1% reading, ±1 count;
1 ¬ 500 ohms: ±1.5% reading, ±1 count
test voltage 36 Vdc max
test current range auto range, 40 Amperes max
display back-lit LCD Screen (20 characters by 4 lines); viewable in bright sunlight and low-light levels
printer 2.5-inch wide built-in thermal printer
keypad rugged membrane keypad (10 alpha-numeric keys, 6 function keys)
internal test record storage stores 63 test records of 48 readings each
computer interface one RS-232C port
pc software Windows®-based software is included with purchase price
safety designed to meet IEC61010 (1995), UL61010A-1, CSA-C22.2 standards
environment Operating: -10°C to +50°C (+15°F to +122°F); Storage: -30°C to +70°C (-22°F to +158°F)
humidity 90% RH @ 40°C (104°F) non-condensing
altitude 2,000 m (6,562 ft) to full safety specifi cations
cables three 50-foot test cables, ground cable, power cord and cable bag
options transportation case
warranty one year on parts and labor
NOTE : the above specifi cations are valid at nominal voltage and ambient temperature of +25°C (+77°F). Specifi cations are subject to change without notice.
ordering information
Part number WRM-40 WRM-40 and cables
Part number WRM-40 CASE WRM-40 shipping case
Part number WRM-40 50-FT CABLES 50-foot test cables
Part number TP3 2.5-inch wide thermal printer paper
33
Page 4
Instruments designed and developed
by the hearts and minds of utility
electricians around the world
Vanguard Instruments Company, (VIC), was founded in 1991.
Currently, our 28,000 square-foot facility houses Administration,
Design & Engineering, and Manufacturing operations. From its
inception, VIC’s vision was, and is to develop and manufacture
innovative test equipment for use in testing substation EHV circuit
breakers and other electrical apparatus.
The fi rst VIC product was a computerized circuitbreaker analyzer,
which was a resounding success. It became the forerunner of an entire
series of circuitbreaker test equipment. Since its beginning, VIC’s
product line has expanded to include microcomputer-based, precision
micro-ohmmeters, single and three phase transformer winding turnsratio testers, transformer winding-resistance meters, mega-ohm
resistance meters, and a variety of other electrical utility maintenance
support products.
VIC’s performance-oriented products are well suited for the utility
industry. They are rugged, reliable, accurate, user friendly, and
most are computer controlled. Computer control, with innovative
programming, provides many automated testing functions. VIC’s
instruments eliminate tedious and time-consuming operations, while
providing fast, complex, test-result calculations. Errors are reduced
and the need to memorize long sequences of procedural steps is
eliminated. Every VIC instrument is competitively priced and is
covered by a liberal warranty.
Vanguard Instruments Company, Inc.
1520 S. Hellman Avenue • Ontario, California 91761, USA
Phone 909-923-9390 • Fax 909-923-9391
www.vanguard-instruments.com
August, 2012
Loading...