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Digital Output Wiring

Digital output has an open collector switching transistor with common IO Ground.
In most cases a power source for external device must be provided.

Connecting Digital OUTPUT to a NPN-compatible PLC device input (biased)

Output State Output switch state Input state
ON Sourcing current Pull up (energized)
OFF Relaxing Not energized

Figure 1. - Connecting Digital OUTPUT to a NPN-compatible PLC device input (biased)


Important Note:
If using this configuration take into account that Common Ground pole is biased by power supply also for Digital Input!


Connecting Digital OUTPUT to a NPN-compatible PLC device input

This type of connection is possible only when opto-isolated input is used (bidirectional in some cases) or when only one general opto-isolated input is used.


Output State Output switch state Input state
ON Sourcing current Pull down (energized)
OFF Relaxing Not energized

Figure 2. - Connecting Digital OUTPUT to a NPN-compatible PLC device input - more bidirectional inputs used


NOTE:
In this case bidirectional opto-isolated input must be used


Figure 3. - Connecting Digital OUTPUT to a NPN-compatible PLC device - single input


Connecting Digital OUTPUT to a PNP-compatible device

Output State Output switch state Input state
ON Sinking current Not energized
OFF Relaxing Pull up (energized)

Figure 4. - Connecting Digital OUTPUT to a PNP-compatible device


Pull up resistor might be calculated as follow:
R=(Vpsu - Vinput) / Iinput


Where:
Vpsu - power supply voltage. Must be higher than required input amplitude
Vinput - required input amplitude
Iinput - input driving current (corresponding to input amplitude)


NOTE:
Take care about appropriate resistor power rating P(R)>(Vpsu - Vinput) * Iinput

Output Wiring Example: LED Driving

LED might be driven directly by camera digital output.
Only series resistor must be used to set LED current.

Figure 5. - LED Driving


LED series resistor might be calculated by following equation:

R=(Vpsu - Voutput - Vled) / Iled


Where:
Vpsu - power supply voltage (5V to 24V)
Voutput - voltage across digital output pins (see.Output transfer characteristic)

Vled - LED forward voltage (see table below)
Iled - LED current


NOTE:
Take care about appropriate resistor power rating P(RES)=Iled*Iled*R


Typical LED forward voltage

LED Colour Vled (typ.) Vled (max.) Note
Standard Red 1.7V 2.1V
Super Bright Red 1.85V 2.5V
Low power Red 1.7V 2.0V
Orange 2.0V 2.1V
Yellow 2.1V 2.2V
Green 1.9V 2.5V
Emerald Green 2.1V 2.7V
Blue 2.5V 3.7V
White 2.8V 3.8V
Infra-Red 1.3V 1.8V Optocoupler

Output Wiring Example: Inductive load (Relay) Driving

Do not connect inductive load RL directly to Camera Digital Output.
Transistor has to be used to prevent damage of output.
See image below for possible inductive load driving.
Resistor R can be connected to Digital Outputs and power supply to provide necessary bias current for transistor.
You should also use external diode to protect transistor from over voltage while disconnecting inductive load.
Keep in mind that this connection has an inverted logic.
Current will flow through load at start of camera.

Figure 6. - Inductive load (Relay) Driving (inverted logic)


To get positive logic you can use second bipolar transistor.

Figure 7. - Inductive load (Relay) Driving (non-inverted logic)


Output Wiring Example: Driving trigger input of strobe controller

Digital output might be used to drive strobe controller according table below.


Driving trigger input of strobe controller

Trigger polarity Opto-isolated controller input Output delay Wiring Description
Positive edge Yes 0.5us Figure 1
Negative edge Yes 0.5us Figure 3
Positive edge No 155us Figure 4 Not recommended in cases when short delay time is required. Output delay is much longer than in other wiring examples. Use external pull up in case that no pull at controller input is used.
Negative edge No 0.5us Figure 4 Note that external pull up is not used in this case. Assume that internal pull up at the controller input is used.