Hi I am using Delta DVP-20-SX2 PLC and Weintek MT8071IP HMI. I am experiencing a very strange issue. Whenever, i connect PLC and HMI to the same power source the PLC seems to freeze and does not perform required operations. However, when i connect PLC and HMI to separate power sources, the PLC keeps on performing its normal operation and updates data on HMI regularly. I have searched various forums and could not come up with an answer to why connection with same power source freezes PLC. Any help will be highly appreciated as it is not feasible to connect separate power sources for PLC and HMI.