A failing transformer can lead to long periods of unplanned downtime and costly replacement work. From insulation resistance testing to , regular transformer maintenance is essential to ensuring your electrical system reaches its maximum operating life.
Measures a power transformer’s electrical transfer functions over a wide frequency range to assess the mechanical integrity of its core, windings, and clamping structures. This allows us to identify problems, such as winding deformation, displacements between high- and low-voltage windings, partial winding collapse, shorted or open turns, faulty grounding, core movement, broken clamping structures, or other internal connection issues.
Used to evaluate wiring insulation. High potential, or ‘hipot’ testing, determines a device’s ability to operate safely during rated electrical conditions. Current going through a device must be less than a specified threshold at the required test potential and time duration to meet the dielectric withstand requirement.
Because transformers are exposed to vibration, anything from poor design/assembly to overloading can create problems or faults. Winding resistance measurements allow technicians to calculate the I2R component of conductor losses, calculate the winding temperature at the end of a temperature test cycle, and provide a based for evaluating possible damage while in the field. These readings test for differences between the windings and for open connections.
Used to evaluate insulation in bushings or between windings. As insulation ages, degrades, and allows water to enter, the amount of energy that is converted to heat in the insulation increases. This rate of loss is the dissipation factor. Our thorough testing can help identify insulation degradation earlier for a more immediate response.
Insulation damage can result in shorts between turns, thus reducing the number of turns and altering the turns ratio. Measuring the extent of that deviation from the baseline ratio indicates winding deterioration.
Uses an insulation resistance meter to detect insulation punctures. Will also show the amount of moisture that has entered the insulation, the leakage current on the moist or dirty areas of the insulation, and any winding faults/deterioration.
Since oil is used to cool the transformer and insulate internal components, a sample can contain a good amount of diagnostic information. An appropriately gathered oil sample, when analyzed, can help determine breakdown voltage (dielectric strength), moisture content, dissolved gas analysis, and oxidation.
We also have the field expertise to ensure your equipment is in compliance with all NERC/FERC Reliability Requirements. Non-compliance with NERC/FERC requirements can be costly to your business. Delta’s experienced maintenance technicians help our clients meet those standards with reliable relay testing and system verification.