Posts tagged protection
Today we are providing power for a small (25 stall) event at Ravensbourne on Level 4. For this event we were asked to provide power for 30 stalls and a few lights, all requiring hot power. Each stall was provided with 2 x 13A socket with enough power to run a couple of TV’s and Laptop’s each up to a maximum of 16amp’s per stall.
The events main supply was from a single 125A 3ph which was then split down to two 63A 3ph supplies, before being split down to individually protected 16amp circuits for each stall. This gave us plenty of protection against overloads as well as surges and faults. The system has fault protection at 3 levels before it tripped out the whole event, each 16A feed has its own RCD, each group of 18, 16A sockets had there own 63A 3ph MCB protection and the whole event had 125A 3ph RCD and MCB protection at supply and in distribution.
The bulk of the event was cabled using 6 way 2.5mm SOCA with Fan in’s and fan outs at each end, this provided an easy rig and de rig with only 6 SOCA’s being run out to the required locations, and only 3m and 5m 16A extensions to provide final distribution from the fan outs.
Each stall could pull up to 16A with out tripping the individual circuit , but if all 25 had pulled the full 16A, they would have tripped out the incoming breakers as the supply is only protected at 125A 3PH, but 25 stalls all at maximum load would pull 133.3A per phase. Due to the fact that most stall’s were only running a laptop and possibly a tv or small projector, this limit will never be reached, even if a few stalls do draw the maximum available.
During the event today we took some current readings on our main distro and each phase was so low it was unreadable on the meter and the meter’s range was from 50A to 200A.
Today also used the exact kit we have specified for the upcoming 3D Storytelling Conference in late March, and provided a useful insight into any problems we may come across when we rig the next event, in the same space.
Photos after the break: