F80T5HO (60" lamps) require an ICN-1S80 ballast. It is a single lamp ballast. I am not aware of a correct ballast that will drive either 2 or 4 F80T5HO lamps. Most other sizes are either ICN-2Sxx or ICN-4Sxx, running either 2 or 4 lamps repesctively. You can run less than the xSxx (e.g. 1 lamp on 2Sxx) but cannot run more than the stated number, nor can lamps of other wattages be run on the ballast.
When shopping for T5/HO ballasts it is important to note that the lamp designations (e.g. FxxT5HO; FxxT5/HO & FxxT5-HO are the same as the first) are standarized. If the designation is not in that format (i.e. FT36/39w) it is not a T5HO lamp. Of course FxxT8 and FxxT12VHO are not T5HO lamps either. FxxT5 and FxxT5VHO are separate specifications as well.
Lamp designations do not cross reference as they are standardized, however ballasts do cross-reference, between various manufacturers. The type of lamp determines the type of ballast needed (by lamp specifications,) however there is no regulation on the ballast manufacturer/lighting packager/reseller, e.g. they can put FxxT5HO lamp type on any ballast they want too. (results in T12VHO ballasts saying they can run T5HO lamps, and instant start ballast saying the same.) So it is best to use a "cross-reference" when selecting a ballast, rather than the ballast label in some cases; but if the label does not say: Programmed Start and Lamp EOL Protection, it is NOT a T5HO ballast.