i have service cached with 15 scales how to my service show only 14 scale(javascript) (hide max scale)
Check out the answer to this StackExchange question. It restricts the extent but you could use the same method to restrict the zoom to a map cache level of detail.
It would be better if you could hook into the map zoom-start event and cancel the event if it exceeds your level of detail but I am not sure if this is possible.
This sample shows how to restrict the map to specified Levels of Detail (LOD)