Sterilight Ballasts / Controllers. All Sterilight® ballasts have an electronic design, offering constant current output to the UV lamps. This constant current allows for consistent UV output, which is what makes for an ideal UV system. The ballasts are designed to deal with variations in voltage and frequency, as well as protect the UV system from electrical transients (brown-outs and current spikes). All Sterilight® ballasts and controllers offer both an audible and visual alarm (with the Copper series being the exception, having only a visual alarm), allowing for simple troubleshooting in the field. All R-Can electronic ballasts hold electrical certification from a recognized third party (ie.CSA) before going out to the customer.