Greetings dear aspirant,

The candidates who pass X Standard or equivalent examinations with Mathematics and Science subjects are eligible for admission into Polytechnic, whereas candidates who pass XII Standard or ITI examinations only are eligible for Direct Second Year Admission (Lateral Entry). There is no age restriction to join the Diploma Courses in Central Polytechnic Chennai.

https://cptchennai.ac.in/criteria/

You can have a glance at the admission criteria required for diploma courses from their official website.

Hope I've cleared your doubt!!

All the best for your future career