If the PXL system will be exceeding 32 doors then an additional hub will be needed. To ensure that setting up and administering access rights is as simple as possible you should ensure that multiple hubs are added to the same site. So, for example: PXL Hub 1 will be added to PXL Site 1 (and will have 32 doors), PXL Hub 2 should also be added to PXL Site 1 - so you have 2 hubs on Site 1.
This is because access rights and time schedules are specific to sites - so you should minimize the amount of sites on a system wherever possible. An example would be the Total Access group. If a cardholder/credential needs access to every door and there are multiple sites you would need to create Total Access - Site 1 and Total Access - Site 2 and then assign both sites to the credential.
IMPORTANT NOTE: If there is a single RS-485 network in Doors.NET that exceeds 32 doors, an additional LAN-520 module would need to be added to the network (and a new primary controller). So, for example; at the 33rd door, the controller will need to be disconnected from the existing RS-485 network and would then need to be addressed as a primary controller (controller #1). This would become the second physical PXL RS-485 network - which would then be added to the second PXL-configured hub.
The diagram below shows three physical PXL networks, each network has a controller #1 and a network of up to 32 doors. In any combination of PXL 1-door and PXL 2-door controllers (using SB-593s). Assuming each network has 32 doors you would need 3 individual hubs and each hubs is added to Site #1 in Borealis.