Compact Series ITV0000 Electro-Pneumatic Pressure Regulators work on the principle that when the input signal rises, the air supply solenoid valve turns on. As a result, part of the supply pressure passes through the air supply solenoid valve, and changes to output pressure. This output pressure then feeds back to the control circuit through the pressure sensor. Pressure corrections within the ITV0000 continue until the output pressure becomes proportional to the input signal, enabling output pressure that is proportional to the input signal.