The Desigo PXC4/5/7 controller is designed as a free programmable HVAC controller which can be expanded to the maximum of 400 I/Os with additional TX-I/O modules.
Please refer to the datasheet:
PXC4: PXC4.E16 Automation stations Data Sheet
PXC5.E24: PXC5.E24 Automation stations Data Sheet
PXC7: PXC7 Automation stations Data Sheet
The Desigo PXC5.E003 is a programmable integration controller used for system-level functions like alarm routing, system-wide scheduling and trending, device supervision, stronger integration capabilities, and embedded BACnet routing.
Please refer to the datasheet:
PXC5.E003: PXC5.E003 System controller Data Sheet
The device must be online to access web interface and update firmware.