It is best to compose for the standard carillon of four octaves.
Some carillons have the low B flat like Albany.
There are only about 12 carillons in the world that go to the Low G while others have more notes on top. If writing these notes, ossia should be provided for the standard 48 note carillon. The work should be composed with the traditional mechanical hand-played action. Overtones need to be considered when writing for carillon. There is a significant minor third overtone, especially in lower bells.