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We are highly experienced in the repair, maintenance, and testing of transformers.  From smaller dry type transformers up to your largest liquid-filled main incoming substation transformer, we have the experience to maintain the value of your equipment and the personnel available to identify and formulate multiple choices for restoration of power when faults occur.  Our staff of technicians and specialists is prepared to assist you with every stage of your transformer’s life cycle including on-going testing, maintenance, repair, replacement, and acceptance testing.


Trans_1_TesterThe most common tests that should be performed on your transformer includes; power factor or dissipation factor, polarization index, dielectric absorption, transformer turns ratio (TTR), insulation resistance test (megger), infrared, insulator inspections, evaluation of connections, oil circulation checks, and oil analysis.  The results of many of these tests can be reviewed and trended over time to provide a history of the condition of the transformer, which can clearly highlight possible weaknesses.  While we are proficient at conducting all of these tests, in cases where you have collected the data yourself or through a third party, we are still happy to help evaluate the test results and offer our expert advice. 

Of course, once your transformer has experienced a problem or has seen a fault, the problem becomes a different ballgame.  At that point, our testing is performed on an emergency basis with numerous other troubleshooting activities.  Rest assured, we have all the necessary equipment calibrated to our stringent requirements to ensure that we can quickly assess the condition of your transformer in response to an emergency phone call.  In multiple cases to help diagnose the condition of our customer’s transformers, our dedicated technicians have personally delivered oil samples to the test laboratory to expedite test results.

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gasket_1Transformers can experience a variety of fault conditions; and as your power system experts, we can assist you with resolving these faults with repairs or replacements.  While the root cause may stem from a number of conditions, a typical work scope to repair a leaky bushing would include de-tanking the transformer, removal of the bushing, manufacture a replacement gasket, and reinstallation of the bushing.  The insulating fluid would be returned or replaced and the transformer would be pressurized with a nitrogen blanket to verify the integrity of the seal.  When the transformer seal has been validated, the transformer will be electrically tested prior to coming back online.

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transformer_fansIf your transformer is experiencing higher than appropriate running temperatures, we offer a multitude of tests and maintenance actions to isolate and eliminate the cause of the issue.  A typical action plan would include cleaning, radiator flow evaluations, fan system integrity checks, electrical tests, and expedited oil analysis.  If these tests do not clearly indicate a common source to the issue, we use our power monitoring equipment to evaluate and analyze the actual load on the transformer.

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Tap Changers

If your transformer includes an automatic load tap changer (LTC), our expert technicians will troubleshoot and repair the entire system including the controls, driver motor and contacts.  Our testing of these devices will include the transformer turns ratio test (TTR) at all tap positions.  Due to the large number of tap positions, this commonly exceeds thirty tests and we evaluate them all!  To minimize your downtime, we have developed extensive resources to supply replacement components for these complex devices.   

Many of your transformers are equipped with a no-load tap changer.  When de-energized, this allows the transformer turns ratio to be manually adjusted to accommodate the varying conditions in your power system.  While these systems are typically simple, they do cause issues that require immediate attention.  We repair the contacts of these units or eliminate the weak link from your system by creating dependable physical connection.

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bushing_1Should normal visual inspections identify an issue with a bushing, we are experienced at using third party vendors for the remanufacturing of your porcelain and polymer bushings.  The rebuilt bushing would be subject to a full battery of electrical tests prior to installation.

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Oil Service

Regarding your insulating oil, our service offering is not limited to oil sampling, testing, and evaluation of the oil samples.  We also offer oil filtration services that can remove carbon contaminants from the oil; this can greatly extend the life of your oil, insulation, and transformer.

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In all cases, our team can help identify methods to extend the life of your transformers and minimize the risk of unexpected outages.  And in those rare cases where a large transformer needs to be replaced, we can help find a new or used transformer that will meet your requirements.  Partnering with us for your transformer needs ensures that the right team is inspecting, testing, and maintaining the transformers in your power system.

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