The relay extension set consists of a relay board and the connection cable to the Data Display Controller
The connection is very simple.
Open the DataDisplay Controller (loosen / cut the bond):
Remove the board carfeully upwards and insert the connection cable. The plug fit only in one direction, do not forcefully try to push the plug in!
Insert the board back into the housing and close the lid. Fix with a strip of adhesive tape because the locking mechanism has been designed for a one-time close.
The relay extension set has one "Normally Closed" and one "Normally Opened" contact per relay.
This are the connections:
NC = Normally Closed
NO = Normally Opened
COM = Connection between NO or NC