Monthly Archives: August 2016

The Advantages of Permanently Installed Automatic (PIA) IR Testing equipment:

IR testing devices have made significant technology developments over the years from the first portable hand held type models. The latest designed systems now have the ability to be permanently installed in the motor control cabinets or generator switchgear and can perform automatic continuous inline IR testing on the equipment whenever it is DE-energized. This allows maintenance personnel to better obtain the true IR leakage current in a more accurate and safer manner. Some of the major benefits to this new technology are as follows: 1. (PIA) IR testing systems are permanently installed and have the ability to perform a continuous inline IR test while the equipment is offline and isolated from the power source. This provides the means to capture both the real time IR values as well as the overall IR values. The (PIA) IR testers can detect any changes in the IR readings that may occur quickly, as well as those that occur over a longer period of time. This data can then be used to trend and track the electrical condition of the equipment’s insulation thru a DCS or SCADA type of system. 2. (PIA) IR testing systems provide a significant increase in personnel safety because of their automatic “No Hands On “testing and display capabilities. The systems are permanently installed inside the MCC or Switchgear cabinets and they no longer require maintenance personnel to access the inside of the cabinets to perform manual IR testing. The (PIA) IR testers help maximize a company’s NFPA 70E compliance for personnel safety. 3. The ability of (PIA) IR testers to perform insulation testing over long periods of time makes the test readings temperature independent and so they do not require a temperature correction. This type of overall IR test data is far more informative than the data gathered during a spot type manual IR test. An overall long term IR test is the only way to capture the true leakage current occurring in the equipment’s insulation. 4. (PIA) IR testers provide an electronic method of tracking and trending the equipment’s electrical insulation condition, which is important to be able to accurately predict when a failure may occur. This (PIA) IR testing method provides far more consistent test results which helps eliminate false data during testing of the insulation. 5. (PIA) IR testers provide the ability to perform a pass/fail test on the equipment before each and every start up, which is the time when most electrical failures do occur. A manual IR test would not be feasible before every start up for obvious reasons. Performing an IR test on the equipment before every start up will help eliminate catastrophic electrical failures that can lead to expensive rewind repairs and unscheduled plant downtime costs. Equipment Reliability and operating life can now be maximized with the use of these type of IR testers. 6. (PIA) IR testers are the only devices capable of detecting and recording both the hot IR readings along with the cold IR readings. A manual IR test can never be performed in time to capture the hot IR reading due to access time restraints. The reason that the hot and cold readings are important is because of the fact that good insulators have a negative temperature coefficient which means that their IR readings are then inversely effected by temperature. So the higher the temperature of the insulation the lower the IR reading. If the insulation is in good condition the IR reading will then rebound very quickly as soon as the temperature returns to the ambient temperature. This data is very useful in both determining the age of the insulation materials, as well as predicting the amount of operating life that remains in the insulation.