Niko Access Control - Digital - How many door locks can be controlled? And how are they controlled?

You can control 2 door locks per external unit. and also 2 locks on the controller itself. 
This can be connected in several ways

• The door lock can be connected to the external unit or to the controller.
• It is possible to power a 12V max 1A door lock (max 0.5A on the external unit) directly through the installation. Door locks with a different working voltage can be controlled through an extra power supply via the potential-free contact.
  A max switching current of 1A should also be taken into account here.
• With software version 2.0 or higher, all door contacts can be controlled separately.