Cheran exp is based in coimbatore. Example rake 1 leaves Coimbatore in Monday to Chennai 500km then to TVM 900km arrives on Wed . TVM Wed dep to Chennai 900km Thrusday leaves to Coimbatore 500km total 2800km round trip undergoes Primary Maintainance and keaves on Friday. Mon, Tues, Wed, thrusday total 4 rakes will undergo PM arriving from Friday at Coimbatore similarly other daily trains of SR operating ftom Egmore