Pull-up / Pull Down
You can configure Opto Trigger 5 according to the electrical source of the incoming signal:
- Use pull-up (10 kΩ) to receive signals from NPN transistors (open collector, open drain).
- Use pull-down (10 kΩ) to receive signals from PNP transistors (open emitter, open source).
In most application scenarious, you will need to configure OPTO trigger 5 to pull-up .
Pull-up variant:
Pull-up is the default setting. The DIP switch for transistor mode (switch 3) is in OFF position. The LED P DN is OFF:
Pull-down variant:
The DIP switch for transistor mode (switch 3) is ON position. The LED P DN is ON: