For pure CCP problems it is advised to excite the system with a power source (see Electric Excitation) because it makes convergence easier. On the contrary, in ICP/CCP reactors the problem becomes more difficult to solve when using the power source option. For ICP/CCP models it is recommended that the RF bias to be excited using a voltage source. As an example for CCP reactors it is advised to set the Terminal type to Power in the Metal Contact but for ICP/CCP reactors it is advised to set Terminal type to Voltage.