So you are playing with the rules from Supplement #1, because that is where that rule is?
No, the S-400 is not within 10 hexes of the ADF tracks, since they are not on the map.
So I can understand this answer from a rigid RAW view point. However S-400 batteries are considered within 10 hexes of installations on the strategic map. I am curious why the S-400 batteries would be unable to protect themselves?
Its pretty minor in the broad scheme of things, and requires the Rules Supplement anyway, but there is already some use of these Supplemental rules in GSR 5.5.3