Introduction
Basic
theory of insulation; Dielectric loss, Power factor, Dissipation factor;
GST, GST-G and UST mode for
testing.
Testing Techniques
AC
test and DC test, advantages and disadvantages of each.
Transformer
Testing
IR,
AC or DC High-Pot, tan d,
TTR, Polarity, Voltage balance, Induced potential, DGA, DC winding
resistance;
Acceptable values.
Oil
- Definition
of terms used in oil characteristics; Acceptable values for BDV, tan d,
Specific resistance,
Neutralisation value, Interfacial
tension, Gas content, Oil filtration techniques-
Fuller's earth, Enervac and Velcon
system; DGA (Dissolved Gas Analysis), Principle, Roger's
method, Limiting value of Hydrocarbon
concentrations, Case studies, Condition
monitoring, Recommended test and periodicity.
Generator/Motor
Testing
IR,
PI, DC High-Pot, Step voltage, tan
d,
PF-tip up, DC winding resistance.
Switchgear
Testing
Visual
and mechanical inspection; IR and DC High-Pot in Circuit Breaker open and
closed position, tan d,
Contact resistance, Time travel analysis, Thermo graphic survey, CT
& PT testing, Protective relay and functional
operation.
Cables
and Accessories Testing
IR,
DC High-Pot, tan d.
Battery
system Testing
Definition
of AHR rating and Volt / Cell for Lead acid and Ni-Cd Batteries; Periodic
inspection procedures
for
Battery and Battery Chargers; Service test for given load
cycle, Connection resistance test and Battery
impedance test.
Commissioning
and Startup of Electrical System
Pre
Commissioning checks of Generators, Motors and Transformers; Connectivity
and Phasing out; Generator
dry out; Short-circuit heating, and testing of Protective Relay
operation; Synchrochecks.
Documentation
and record keeping
Typical
test format for periodic maintenance testing.
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