WJ-11/RY51/WJ-12/RJ-12 are a series of controllers and I/O modules working as a part of building management system for HVAC control. They enhance seamless interlock functions between devices, are highly reliable and have a robust design. A flexible combination of devices (WJ-11:1 item, RY51:19 items, WJ-12:13 items, RJ-12:5 items) greatly enhances facility control and improves the energy-saving performance of buildings. Smartphone with Near Field Communication will enormously reduce on-site engineering works such as parameter settings and data check.