TAC Xenta 911 is intended for use with most TAC units supporting dial‑up. The IP address of the "dialed‑up" unit will then replace the telephone number. This makes it very easy to save money by eliminating telephone line costs. The fast dial‑up time, typically less than two seconds, provides the feeling of a directly connected network. The TAC Xenta 911 is quick to install and is easily maintained, using a web browser on the TCP/IP network. Its default values are set for TAC Xenta connection, and it is pre‑configured for most TAC products. The TAC Xenta 911 contains HTML pages providing comprehensive on‑line help. The TAC Xenta® 280 is a family of programmable controllers designed for zone control or small‑sized heating and air handling systems. A TAC Xenta 282 controller contains basic HVAC functionality including control loops, curves, time control, alarm handling etc.