Hi Brijesh, Welcome to EasyEDA. I assume from your question that you want to simulate the 3cxp5000a7 rather than just draw it in a simulation? 1. The Triode symbol is in the EasyEDA Libs in the left hand Navigation Panel. You can use this for simple schematic drawings as well as for simulations. 2. To see how to inlcude triode models in a simulation please see this project: >https://easyeda.com/project_view_Valve-Tube-examples_05ZhzR9rJ.htm 3. Please note however I am not aware of anywhere that you will find a simulation model for the 3cxp5000a7. Yu may need to read some of the links in the example or here: >http://www.normankoren.com/Audio/Tube_params.html You may be able to run his Matlab program (Tuparam) in Octave: >http://www.gnu.org/software/octave/ There is an online version here: >http://www.online-utility.org/math/math_calculator.jsp :)