LumaSMART
®
User Manual
Introduction
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If loading becomes overwhelming and the transformer cooling equipment is unable to maintain the winding
temperature at a safe value, other controller relays with higher setpoints can be used to activate alarms or trip the
transformer.
2.4.3
Increased Transformer Loading to the Safe Maximum
Due to the relative inaccuracy of estimating WTI devices based on top-oil temperature, transformers must be
conservatively loaded to ensure the winding temperature is maintained below a safe value. Utilities with
experience using the previous generation LumaSense WTS-22 systems estimate that an additional 10% loading can
be achieved by accurately knowing the winding temperature.
2.4.4
External Communication and Monitoring Connections
The LumaSMART controller is available with analog outputs and serial digital interfaces (RS232, RS485 and
Ethernet reporting via ASCII, IEC 61850, Modbus or DNP3) for communicating with SCADA and other data-logging
systems.
2.4.5
Extract Additional MVA Rating Existing Inherently in Every Transformer Design
The LumaSMART controller unlocks additional MVA, which is quite valuable during routine and emergency
situations. The key is to gain additional transmission capabilities without damaging the equipment. Precise winding
hot spot measurements by the LumaSMART controller allows MVA loading to be maximized under operational or
transient conditions. Conservatively, an additional
5 to 10% loading is available from a typical power transformer.
Operating decisions can be based upon maximizing economic returns of existing assets without sacrificing
transformer life or providing additional transformer capacity. System capabilities are known and reliability is
protected on a real-time basis as the dynamic system loading occurs.
Additional savings can result from detecting external and internal transformer cooling problems early. Internal
problems can be ascertained only by an internal inspection and the results are often questionable. Direct fiber
optic hotspot measurement provides an accurate profile of the internal cooling system efficiency over the
transformer life.
