Velleman projects K8090 Assembly instructions - Manual (Page 8)

8
The card uses a separate supply for the relays and one for the board microcon-
troller.
Test 1:
• Connect a power supply of 9 to 10Vac or 12 to 14Vdc (minimum 500mA).
• The power LED should turn on.
• The USB power LED will also turn on (indicating that the microprocessor power
is ON).
• Push the buttons and the relays should activate.
Test 2:
• Disconnect the power supply.
• Connect the USB port to the PC.
• The USB power LED should turn on.
• Pressing the buttons will make the output indicator LEDs turn on, but the relays
will not activate.
Now the card can be used with all connections.
It is possible to power the card through USB only, but the relays will not activate.
The relay indicator LEDs will work fine.
This mode can be used for software testing.
Check our web site to download more program examples.
19. Test and connection
Test & connection