IEC 61822:2009 specifies the requirements for a Constant Current Regulator (CCR) having a nominal output of 6,6 A for use in an aeronautical ground lighting constant current series circuit. However, CCRs may be manufactured which have a different power rating (kVA) and current steps than those specified in this standard in order to be used on existing circuits. This standard should be applied where appropriate for these CCRs. This second edition cancels and replaces the first edition published in 2002. It is a technical revision. This edition includes the following significant technical changes with respect to the previous edition: a) revision and update of terms and definitions; b) addition of new paragraphs, such as "Nominal output current range and tolerances"; c) modification of some paragraphs, such as those related to "Local control" and "Remote control"; d) deletion of some paragraphs, in particular "Power transformers" and "Output current indicator".