Johnson Controls Electronic HVAC Controllers
Johnson Controls System 450™ digital electronic controls easily assemble to provide reliable control of temperature, humidity and pressure for a wide variety of HVACR, commercial and industrial process applications. The conveniently designed modules provide a field-configurable out-of-the-box solution. Most modules can control temperature, humidity and pressure simultaneously. A single C450 control module can be set up stand-alone or 
connected to expansion modules to connect up to ten on/off relay and proportional analog outputs, based on any of the three inputs. Control modules with Communications enable connection to Modbus or Ethernet networks for remote monitoring and set up. The Modbus module is an RS485, RTU compliant slave device. The Ethernet module has an integral web serve that can deliver pages via direct connection, on your LAN or across the Internet.
