Modular controller for a building management system

A building system, comprising:

• equipment that affects or senses an environment within a building;
• a controller device comprising:
• a base comprising a first processor and a base interface, the first processor being configured to provide control operations for a device in the building system;
• and
• a first module installable on and removable from the base, the first module comprising a second processor and a first module interface for receiving power from and communicating with the base via the base interface, wherein the first processor queries an address from the second processor of the first module at power up;
• and
• a second module installable on and removable from the base, the second module comprising a third processor and a second module interface for receiving power from and communicating with the first module via the first module interface, wherein the first module acts as a serial pass-through to send address arbitration signaling to the second module.

A method for monitoring or controlling a device in a building management system (BMS), the method comprising:

• providing a base comprising a first processor and a wireless base interface, the first processor being configured to provide control operations for a device in the BMS;
• installing a first module installable on the base, the first module comprising a terminal block and a first wireless module interface for receiving power from and communicating with the base via the wireless base interface;
• installing a second module installable on the base, the second module comprising a second module interface for receiving power from and communicating with the first module, wherein the first module acts as a serial pass-through to send address arbitration signaling to the second module and
• coupling the device to the terminal block.