The concept of Condition Monitoring is to enable condition-based maintenance to be carried out, i.e. the continuous or periodic measurement and interpretation of collected data to indicate the condition of an item and to determine the need for maintenance. Condition monitoring is normally carried out on-line with the item in operation and not subject to any shut-down.

The availability of sophisticated Instruments to record performance information of equipment on-line have allowed measurements to be made for analysis and comparison, thus detailed fault diagnosis is easily achieved and action taken before equipment failure without unplanned shutdown.

Some of the major techniques and applications currently available are reviewed as follows:

Infrared Thermography A non-contact measurement of temperature anomalies on Electrical and
Mechanical equipment, thereby enabling detection of possible faults. Not only
Electrical installations, but important areas like Furnaces, Reactors, Cryogenic
equipment, pipeline insulation, chimney Stacks, bearings, steamlines,etc can
be inspected.
Partial Discharge for Rotating Drives
& Switchgears
Enables detection of potential insulation failure in HV Cable connections,
switchgear, transformers and motors/generators, caused by ionisation of the
air resulting in arcing, tracking & corona, and air voids within solid insulation.
Cable Partial Discharge Testing
(Online & Offline)
Enables detection of potential insulation failure in HV Cables with no
interruption in the system using the Online Test. Upon detection of possible
faults, to reconfirm using the offline methods using Tan Delta and PD.
Corona Inspection Detects Corona and Arcing of Overhead HV insulators to detect faults and
degradation not detectable by visual inspection
LIRA CABLE CONDITION ASSESSMENT Enables detection of the condition of Underground, Subsea and ELV cables up
to 100's of km long.
On-line Motor Signature Monitors condition of motor to detect winding problems, high resistance
joints, stator faults, rotor bar defects & air-gap eccentricity
Power Quality Monitoring Monitors presence of power surge, sag, transient and harmonics in power
supply systems.
Electromagnetic Interference Measure & monitor presence of undesirable low frequency high Magnetic
Field in environment and its effect on equipment and workers’ health.
Vibration Analysis Allows early detection of faulty bearings, unbalance and misalignment
Transformer Oil Analysis (Dissolved
Gas Analysis) and Metals In oil Test
9 gases dissolved in the oil are analysed to determine the type of possible
faults e.g. insulation breakdown, internal arcing, etc. Metals analysis of
transformer oil complements dissolved gas analysis and enables the type of
possible fault to be determined.