Hello,
No, you cannot join in 2nd year of Diploma through Ploycet. Polycet is an entrance exam for admission in various Engineering diploma.The course duration is 3 years.The admission is based on merit in 10th class.A candidate must have passed 10th with atleast 35% with Mathematics as compulsory subject from a recognised board or university in Telangana/Andhra Pradesh.
After completion of diploma you can get admission in B.tech 2nd year through ECET.