The IQ3 controllers are Building Management System controllers that use Ethernet and TCP/IP networking technologies; they are optionally able to use BACnet protocol over IP. Each controller incorporates a web server which can deliver user-specific web pages to a PC or mobile device running internet browser software. If a system is set up with the correct connections, a user with the appropriate security codes can monitor or adjust the controller from any Internet access point in the world. It is also compatible with the traditional IQ system protocol. The IQ3 range consists of DIN rail mounting controllers with from zero to 16 input/output points (expandable up to 128 points by adding DIN rail mounting I/O modules). This flexibility makes them suitable for a broad range of applications. A local PC or display (SDU-xcite) can be connected to the RS232 port.