Procedures for Testing with the DX Host
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Surge Tests Using the DX Host
NOTICE: Review all safety information provided with the equipment and presented in chapter 1 —“General
Operating Information” before setting up or operating.
Confirm that the Baker DX setup procedure has been followed. Refer to chapter 5 —“Setting up the Baker
DX Tester” as needed.
Refer to chapter 7 —“Setting up Fixtures, Test Accessories, and Lead Connections” for information needed
on this topic.
WARNING: To avoid potential for injury or death from electrical shock, properly
discharge high-voltage used in Surge testing from motor windings before
removing test leads.
Surge testing detects insulation damage between the turns of a motor’s winding. This type of
insulation problem cannot be detected by any method other than a Surge test. Surge tests
involve the application of a short-duration, high-level, and fast-rising current impulse to a
winding. This impulse will induce (per Lenz’s Law) a voltage difference between adjacent loops
of wire within the winding. If the insulation between the two loops is damaged or somehow
weakens, and if the voltage difference between the wires is high enough, there will be an arc
between the wires. The Baker DX detects arcs by observing a shift in the surge waveform
produced by the test.
On the Baker DX, the Surge test is performed with an impulse generator, and the resulting
waveform is displayed on the screen. The surge waveform is a representation of the voltage
present across the tester leads during a test.
The indication of a turn-to-turn fault is a shift to the left and/or a decrease in amplitude of the
Surge test waveform as the test voltage increases.
The Baker DX can perform multiple Surge tests. A common test involves multiple coils
configured into windings. Another common test evaluates individual coils. Other tests involve
field and armature coils.
NOTE: Refer to the
Megger Motor Testing Theory Reference Manual
for more information and details on
Surge testing capabilities of the Baker DX.
Surge Test Procedure Overview for Three-phase Coil Mode
The general test procedure for Surge testing includes the following steps:
1.
Ensure low-voltage test leads are not connected and set aside.
2.
Ensure high-voltage test leads are properly connected three-phase coil mode.
3.
Select Surge mode.
4.
Select three-phase coil mode. Coil 1 selected by default.
5.
Press and hold PTT.
6.
Ramp up voltage to test level.
7.
Run test for approximately 10 pulses.
8.
Release PTT.
9.
Select coil 2 and repeat testing process.
Summary of Contents for Baker DX
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Page 10: ...Table of Contents viii Baker DX 71 030 User Guide EN V10 www megger com...
Page 28: ...Baker DX Instrument Overview 18 Baker DX 71 030 User Guide EN V10 www megger com...
Page 38: ...Baker DX User Interface Overview 28 Baker DX 71 030 User Guide EN V10 www megger com...
Page 58: ...Setting up the Baker DX Tester 48 Baker DX 71 030 User Guide EN V10 www megger com...
Page 149: ...megger com 139 RIC Templates Figure 141 RIC template 1...
Page 150: ...RIC templates 140 Baker DX 71 030 User Guide EN V10 www megger com Figure 142 RIC template 2...
Page 155: ...Index megger com 145...
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