Dual Channel Control with Transformer for Variable Input Voltage The CBC-450 is a basic on-off control which supplies 24 or 90 VDC for electric clutch/brake operation. It offers optically isolated switching inputs for start, stop, and emergency stop (E-stop). These controls can be set up to operate the two outputs, alternately (single) or simultaneously (dual). The CBC-450 has a power transformer which will operate with a 120, 220, 240, 380 or 480 VAC input.