Connecting Input Signals; Input Circuit; Connecting A Switch - Contec DIO-0808L-PCI User Manual

3. External Connection

Connecting Input Signals

Connect the input signals to a device which can be current-driven, such as a switch or transistor output
device.
The connection requires an external power supply to feed currents.
The board inputs the ON/OFF state of the current-driven device as a digital value.

Input Circuit

Vcc
Opto-coupler
Vcc
Opto-coupler
* I-xx represents the input pin.
Figure 3.3. Input Circuit
The signal inputs are isolated by opto-couplers (ready to accept current sinking output signals). The
board therefore requires an external power supply to drive the inputs. The power requirement for each
input pin is about 5.1mA at 24VDC (about 2.6mA at 12VDC).

Connecting a Switch

Input plus common (CN1 : 18pin)
I-00 (CN1 : 2pin)
When the switch is ON, the corresponding bit contains 1.
When the switch is OFF, by contrast, the bit contains 0.
Figure 3.4. An Example to use Input I-00
30
Board
Plus
Un-
common
connected
Input pin
Un-
connected
Input pin
Switch
External circuit
External
power supply
12 - 24VDC
Switch
Switch
+
External
power supply
12 - 24VDC
-
DIO-0808L-PCI