Velleman projects K2634 Assembly instructions - Manual (Page 7)

7
Connection
7. Connection
Connect the minus side of the inputs to the open collector outputs of the interface card(s) (see fig.1).
Connect the positive side of all inputs with a control voltage (ex. +9Vdc to 12Vdc). The negative (GND)
of the control voltage must also be connected to the Common (or GND) of the open collector card.
Keep in mind that EACH input of the triac card takes about 12mA from the power supply !
This control voltage has to be COMPLETELY ISOLATED!
To supply the card a separate supply must be used of 9Vdc (see fig. 1)
Connect the supply for the loads to the points VAC. It may range between 24 and 240 VAC.
Fig.1