Megger Baker DX - Partial Discharge Testing Overview and Preparation; Preparing for PD Testing

Procedures for Testing with the DX Host
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3. If a low MegOhm value is measured, inspect the motor for ground wall insulation
damage or determine if some part of the ground wall insulation has failed. Possible
problems include the following:
 Either the slot liner insulation or enamel wire insulation might be burned or
damaged.
 The motor might be full of dirt, carbon dust, water, or other contaminants.
 Connections to the actual coils might be bad.
 The wrong insulation might have been used to connect the coils to the motor’s
junction box.
NOTE: No further testing is worthwhile until you find the reason for low MegOhm readings and make any
necessary corrections.
For more details, refer to Megger Motor Testing Theory Reference Manual, which has supporting
information and details about DC testing capabilities and methods.
DC Test Procedure Overview
The general test procedure for DC testing with the DX host includes the following steps:
1. Ensure low-voltage leads are removed and set aside.
2. Connect high-voltage test leads.
3. Select DC tests mode.
4. Push and hold PTT.
5. Touch Lock PTT icon.
6. Touch MOhm/PI icon.
7. Ramp up test voltage then run test to completion.
8. Conduct Step Voltage test. Ramp up voltage to next step level then touch Step icon.
9. Repeat for each step up to second to last step.
10. Run DC HiPot for last step. Ramp voltage up to proper level then touch HiPot icon.
11. Alternatively, run just the DC HiPot test or a Ramp test.
12. Press lock PTT to release.
13. Save data.
14. Ensure voltage discharges completely before removing test leads or leave test leads
connected if running Surge test next.