Variable Speed Drives
Rolla have been designing and supplying enclosures for Variable Speed Drives and Soft Start Units for many years. Some of the special features to be taken into account include :-
- internal segregation
- interlocking between multiple access doors
- interconnections between devices
- EMC requirements
The pictures below show some of the recent jobs we have completed. All the small wiring is carried out by our panel builder customers, we provide the supporting structure and solid busbar connections.
250KW unit using ABB ACS800 series modular drive, under construction.
900KW Variable Speed Drive - ABB ACS 800 12 pulse
Drive modules in place, can be removed from the front for maintenance.
Outer view of a suite of drives, air inlet ventilation cutouts at the bottom of the doors.
Air inlet vents and outlet fan cutouts on the doors. This is a popular arrangement, but care must be taken with the room ventilation due to heat from all the drives.
Curved drive suite we did for the ODA pumping station in London. This suite had to fit around the internal curve of the building.
This drive is complete and ready for test. Note internal baffling to prevent air recirculation within the enclosure.
1250KW drive, one of 6 for the St. Germans Pumping Station near Kings Lynn.
This is still the largest pumping station in the UK and more information can be found here
View with the doors open. All the doors are interlocked mechanically so they cannot be opened until the drive is isolated.
AC and DC busbars, with high speed fuses.
DC link bars (normally operating at about 700V DC) and special chokes. This is the output stage of a triple module drive.
Complete drive, ready for test.
There is more information and a 400 year history of the largest pumping station in the UK on the Midlevel Website, including some pictures.
Stand alone 900KW drive (12 pulse) - ABB ACS800. One of 3 identical units with associated transformer providing the split phases.
Completed installation. This is one of the largest pumping stations in Welsh Water.
Small soft start unit (Rockwell/Allan Bradley). Wiring not yet complete. Solid busbar connections by Rolla, wiring by others.
Large soft start unit.