Sunny UVT-LTX retrofit in Florida


100 miles south of Miami, energy supplier Keys Energy Services operates the Big Pine substation, home to an old Westinghouse transformer which transforms power from 138kV to 13.8kV. The UVT on-load tap-changer on this transformer has regularly required maintenance. The costs and long downtime periods of this regular maintenance caused major problems for Keys Energy Services. The solution: retrofit with a new VACUTAP® UVT-LTX from MR.

The LTX, which stands for Life Time Extension, transformed an old Westinghouse UVT into a new VACUTAP® RMV-II. Only the load-switching unit, gearbox and motor-drive unit had to be replaced. The housing, contact board, and selector elements of the old UVT could be kept. This also meant that the oil didn't have to be pumped out of the transformer. All in all, this was a low-cost solution for Keys Energy Services, especially since the maintenance interval was extended to 500,000 tap-change operations. Since it is unlikely that this number of tap-change operations will ever be reached in a normal network application such as that used at Big Pine, the tap-changer is now virtually maintenance-free.

Last December, experts from our US subsidiary Reinhausen Manufacturing (RM) visited the site to undertake the replacement. Under the direction of RM service technicians Victor Castano and Nick Pratt, the work was successfully completed in under a week. Transformer components were also replaced in the process. The pressure relief device, displays, and dehydrating breather are now from Messko and are therefore guaranteed to be reliable and maintenance-free.

Not far from Big Pine, the RM staff have replaced another VACUTAP® UVT-LTX at the Big Coppitt substation. The tap changers in both substations are now running with proven VACUTAP® technology from MR. Both systems were back up and running in time for Christmas and were perfectly prepared for the big influx of holiday season tourists.

u.firnhaber@reinhausen.com