The document discusses different controller options for fans, including controllers for EC fans with 0-10V input, compact fans with PWM input, and compact fans with 2/3 wires and no control input. It provides part numbers and specifications for each type of controller, including temperature control ranges, voltage options, and alarm output types. Upcoming controller options are also mentioned, such as a DCP fan controller that allows PLCs to control compact fans and various manual control options for EC fans with 0-10V inputs.