The upgrade was essentially a second phase of initial refurbishment carried out by ELP in the summer of 2004, providing two further CM12 motor controllers, eight more Socapex/C-Form splitter boxes, remote control handsets and multi-point linked Emergency Stop system, in addition to automating the whole system.
ELP project manager Toby Dare's brief was to provide a series of rigging presets for the venue's various show modes, so an Ibex automation system was specified to drive the Out Board motor control distros. To ensure absolute repeatability, all 32 CM Lodestar hoists were fitted with Out Board's optical bi-phase encoders to provide precise positional and directional feedback to the Ibex system.
A total of 16 one-tonne CM Lodestar hoists were used to fly a large downstage grid, under the control of one Ibex PHC+ 24-channel unit and a pair of CM12 12-channel motor controllers with linked E-Stop system. An additional Ibex unit and two more CM12s were used to control a separate upstage system flying four individual trusses off 16 half-tonne CM Lodestars. Out Board specially developed a new version of their optical bi-phase encoder to fit into the smaller half-tonne hoists.
The two pairs of CM12s were installed in separate upstage and downstage roof locations, each with eight distributed splitter boxes to allow for easy patching of C-Form control and power cabling to the adjacent hoists. Long extension cables from the CM12's remote control ports were run to stage-side positions where they could either be plugged into adapter cables to interface with the mobile Ibex rack, or remote handsets for manual control.
(Lee Baldock)