IEC 62386-203:2009 specifies a protocol and test procedures for the control of electronic control gear by digital signals used on a.c. or d.c. supplies, associated with discharge lamps (excluding fluorescent lamps). This Part 203 is intended to be used in conjunction with IEC 62386-101 and IEC 62386-102, which contain general requirements for the relevant product type (control gear or control devices).