[dez250]

If you are planning on hosting an off season competition i would seriously suggest you to get an official FIRST field, which would come with the field electronics. While this may cost a lot for insurance and is normally refunded, barring no damage, see if a sponsor will help out. Also in the long run it probably will be cheaper for if some reason your home brew arena controller surges power to the teams OI, it will start costing you a lot to replace damaged units for teams.