Functionality of BIZ-TH100 Controller can be greatly expanded by adding Relay Outputs.
Outputs port is located on the left bottom side of the Controller and has 2 pin pairs. Pin pairs are labeled R1 and R2, on the front side of the Controller.
Relay Outputs connect to the Controller Outputs port using a supplied 4-pin connector as shown on the picture below (actual connector has no markings):
R1 - Pair of pins for the first Relay Output.
R2 - Pair of pins for the second Relay Output.