9
Connect the Power Supply
Step 6: Connect the Power Supply
The I/O Expansion Board required 12v power to operate. The PCB requires
approximately 50mA when no relays are active, plus approximately 33mA per output.
Wire the power supply to terminal block J8 marked ‘12V’ and ‘GND’.
Two terminals are provided for +12V and two for GND for connecting to other
devices.
LEDs:
Power LED: This will light when J7 is fi tted and power is supplied. If the Power LED
is off, check the power supply for correct operation, and check that all connections
are correct.
CPU LED: This will fl ash during normal operation. If the CPU LED is permanently on
or off there may be power problems or damaged circuitry.
HOST LED: This will light when the I/O Expansion Board is successfully
communicating with the Master i-Net via the RS485 bus.
Important!
•
The power supply MUST be earthed.
•
The power supply must be able to deliver power for all devices connected to
the I/O Expansion Board. Although the current required by the I/O Expansion
Board is low, this will increase as different load devices are activated. The power
supply must be capable to delivering worst case power requirements. Always
allow some contingency when calculating the size of power supply required.
•
After changing any DIP switch settings or jumper positions, the controller must
be switched off and then on again. This is easily achieved by removing jumper
J7, count to 10 then replace it.
