Luxtron has released its ThermAsset2 temperature controller, designed for direct, real-time control for power transformers down to 25 MVA.

The ThermAsset2 is a much sought-after addition to the Luxtron product line, offering a primary controller to monitor hot spots, control cooling, and protection at a cost that is attractive to the apparatus engineers and system operators. Available in two- or four-channel configurations, the ThermAssets offers full control with alarm status indicators for up to six customer-specific relay functions.

This controller offers many of the reliable and proven features found on Luxtron’s WTS-22 and ThermAsset systems, considered the standard for fiber optic temperature measurement of transformer windings in the power utility industry. The same Luxtron Fluoroptic Thermometer (FOT) technology is employed using a lifetime LED light source to activate the sensors. The ThermAsset2 uses Luxtron’s ruggedized probes, which require no calibration over the life time of the transformer. The ThermAsset2 meets 3000 V surge protection requirement (IEEE C37.90.1-1989).

Small- and medium-size transformers often take the brunt of the load in an overload condition and thus are most likely to be damaged without proper control. It is well known and accepted, that winding hot spot temperature measurements are the only safe means to activate the cooling systems (fan and pumps) to provide transformer thermal protection from insulation damage. Conventional winding temperature indicators only “infer” the hot spot by measuring top oil temperature. The ThermAsset2 enables direct, real-time, accurate measurement of transformer winding temperature, thereby providing valuable input to calibrate thermal models and enable dynamic load control. The drift-free, calibration-free nature inherent in the Fluoroptic technology makes these systems suited for use in transformers.