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Electrical Theory & Applications for HVACR
Chapter 5: Automated Control Systems
Page 101
CONTROLLER TYPES
As with all standards, there are different controllers used to adapt system components to the BAS.
The three main types are programmable logic controllers (PLCs), system/network controllers, and
terminal unit controllers.
NETWORK CONNECTIONS
Remote connecƟons to most systems now available require the modem IP address. Most internet
providers connect homes with a dynamic connecƟon in which the IP address will change. If a staƟc IP
address is not available, a Domain Name Service (DNS) must be used to keep track of the IP address
in use.
The following is a graphic representaƟon of the components of a home network with the HVAC
system connected. HVAC controls can be hard wired or connected wirelessly to the home network.