Atec Vanguard_WRM-10 - Manual (Page 2)

WRM-10
lightweight winding resistance meter
The WRM-10 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-10 provides stable resistance readings of very
large transformers by utilizing a 36Vdc power supply capable of output-
ting up to 10 Amperes. The resistance reading of a 100MVA transformer
can be achieved in 5 minutes or less. The unit’s power supply is cooled by
heavy-duty fans designed for continuous operation.
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Built-in Safety Features
At the end of each test, the WRM-10 automati-
cally dissipates the stored energy in the trans-
former. This discharge circuit will continue to
work even if the supply voltage is lost. For added
safety, the unit’s power supply is thermally pro-
tected from over-load damage.
Since the WRM-10 can accurately mea-
sure resistances ranging from 1 micro-
ohm to 2,000 ohms, it can also be used
to measure EHV circuit-breaker contact
resistance, motor winding resistance, or
any low resistance. In addition to mea-
suring the resistance value, the WRM-10
also checks the “make-before-break”
tapswitching sequences of voltage regu-
lators and load tap changers.
The WRM-10 is furnished with three 50-
foot test cables. Each test cable lead is
terminated with a quick-disconnect test
clip.
User Interface
The WRM-10 features a back-lit LCD screen (16
characters by 2 lines) that is viewable in both
bright sunlight and low-light levels. A “turn-and-
push” knob is used to control the unit. A built-in
RS-232C interface port is provided for diagnos-
tic testing and fi rmware upgrades.
WRM-10 connections
outstanding features
• Auto discharge circuit for operator safety
• Auto current ranging from 10 mA to 10 A
• Digital resistance reading from 1 micro-ohm to
2,000 ohms
• Lightweight (27 lbs / 12.2 kg)