Yes, the AXL BK PN is an older model. The modul do not support all local bus modules. For example the AXL BK PN bus coupler is not able to run with the safety local bus modul.
The AXL F BK PN bus coupler is the new model. This bus coupler has for example a Webinterface, supports safety and power supply modules, is able to run PROFINET IRT.
Do not hesitate if you have further questions. Your request is saved in Call number 00077066.