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Checking Test Leads for Broken Sections
Either prior to using the analyzer or at least once a month, inspect each test lead for broken sections. If the analyzer
has a broken lead, it will not work properly and could yield erroneous results. The typical spots where leads break
are within the first six inches from the analyzer panel strain reliefs and 12–18 inches from the clips. There are two
methods to check for breaks in the leads: a manual check and an overcurrent trip test.
Manual Break Check
1. Inspect the lead wire for any cuts or nicks in the wire sheath.
2. Take the clip in one hand and grip the lead wire in the other had approximately 12–18 inches from the clip.
3. Grip the lead wire approximately six inches from the strain relief on the analyzer.
4. Steadily, pull the lead. If the lead stretches, it is broken. If it does not have any give, it is good.
Overcurrent Trip Test
The black ground lead is the most commonly broken lead. This is an easy test to verify if the black lead is broken.
1. Connect all leads together (clip to clip) (three red, one black ground).
2. Place analyzer in either Meg-Ohm or DC HiPot mode. Initiate test.
3. If the analyzer immediately shows an overcurrent trip, the black test lead is good. If the analyzer continues to
ramp up to the test voltage, the black test lead is broken.
Open Circuit Test to Verify Analyzer Operation
While doing periodic testing, there are some instances that the analyzer will immediately trip when first initiating
testing. When this occurs, there is generally some question by the operator if the motor is truly bad or if the analyzer
is operating correctly. A simple open circuit test verifies analyzer operation.
1. Remove all test leads from the motor being tested.
2. Store all leads in a safe place: on the floor, over the edges of a plastic trash can, and so on. Ensure that the test
clips do not touch.
3. Place the black lead away from the red leads.
4. Initiate either a Meg-Ohm or a DC HiPot test.
5. If the analyzer is operating correctly, it will ramp up to the test voltage with minimal leakage current and will not
overcurrent trip. If the analyzer is not operating correctly, it will overcurrent trip immediately as it did when it was
attached to the motor.
6. If the analyzer is operating correctly, reconnect to the possible bad motor and retest. If it is not operating
correctly, contact the Megger Baker Instruments service department for assistance.
Third-party Software Warning
NOTICE: Do not install spyware or spam blockers, screen savers, virus detectors, or wireless internet software to
the analyzer. It will corrupt testing procedures and operations. Many of these types of software packages, when
installed on the analyzer, will continue to poll/use CPU resources of the computer even when not open on the
desktop, which can create conflicts.
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