Baker D30R User Manual - page 45
Surge Testing
12/3/2009 | 71-022 V6
D30R
45
General notices
−
Irregularities, particularly vertical spikes, may be seen the first cycle of the surge wave
pattern. Therese occur most frequently on large, high voltage motors. Do not interpret
these as faults in the windings. Any winding fault will be seen throughout the entire wave
pattern.
−
Do not change the test lead select (TLS) switch while a test is being made. Doing so will
cause arcing and damage of the instrument’s components.
−
Do not switch the function control between Surge and HiPot settings during testing.
−
When increasing the applied voltage during a test, use a higher Volts/Div setting so the
entire wave pattern or trace stays visible on the screen. It is acceptable to change this
setting while testing. The Volts/Div control has no effect on and does not limit the output
voltage of the tester. It only controls the display scale.
−
ALWAYS unclip the test leads. Do not jerk or pull them from the motor leads.
−
Never connect test leads from two or more testers on the same motor. This includes
connection of host and power pack unit leads to the same motor. This warning also
includes lead connections, even for grounding purposes.
−
Do not connect both the resistance test leads and the high voltage test leads to the
motor at the same time.
Surge test setup
Connect the motor as shown in one of the figures above. Connect phase 1 to Test Lead 1,
phase 2 to Test Lead 2, phase 3 to Test Lead 3, and the motor core to the black ground lead.
Note:
these connections are the same as for the HiPot tests of Chapter 5. To HiPot and
Surge Test a motor, the test leads only need to be connected once. The position of the Test
Lead Selector Switch determines which lead is “hot” and which lead is held at ground. The
table below details the test lead configuration for each of the positions of the Test Lead
Selector Switch:
Switch position
Test Lead #1
Test Lead #2
Test Lead #3
Ground
Test select 1
Hot
Ground
Ground
Ground
Test select 2
Ground
Hot
Ground
Ground
Test select 3
Ground
Ground
Hot
Ground
All
leads
ground
Ground Ground Ground Ground
After connecting the motor to the test leads, rotate the Function Knob to the Surge position.
The CRT display should look like the one shown below.
Note:
the “Surge” message at the bottom of the display indicates a normal surge test is active
(and not an AT101 type test or a power pack test).
Before beginning the test, insure that there are no power factor correction capacitors or
surge suppressors in parallel with the motor. Power factor correction capacitors will reduce
the effectiveness of the surge test while surge suppressors will shunt to ground the surge
signal. It is the responsibility for the operator to know what is being tested.
It is the responsibility of the operator to insure that the work area is safe
.
Once the area is clear and safe, press the “Test” button to start the test. Press the voltage
control buttons to ramp the test voltage up or down. As the voltage increases watch the
waveform for sudden jumps to the left which indicates a turn-to-turn short.