The FOFC logic is designed to out perform the One-Third/Two-Thirds concept. As the One-Third/Two-Thirds (1/3 – 2/3) is made to utilize the actuators mechanical end-switches to achieve smoother modulation, the FOFC logic gives far better control by allowing different size actuator applications to use the larger actuator to increase the load and the smaller actuator to fine tune its operation.Using Valve Start Position, Valve Start Delay, and Valve Close Position settings for each of the actuators makes the ESV satisfy every steam and vacuum application’s unique need. These settings are designed to hold the valve partially opened when steam is not needed to reduce piing system stresses and noises.The ESV offers two modulating signals; voltage and 4-20mA current. It can modulate either two voltage actuators or one voltage and one current actuators.