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PN/M-Bus LINK
Operating Instructions, 03/2018, A5E44260928-AA
15
Functions
4
4.1
Cyclic and acyclic data exchange
PN/M-Bus LINK is always the M-Bus master. The functions of the PN/M-Bus LINK enable
you to read measured data from connected M-Bus devices. To do this, the M-Bus functions
"SND_NKE", "SND_UD" and "REQ_UD2" are implemented in PN/M-Bus LINK. It is not
possible to configure or write to M-Bus devices.
Communication paths
The following figure shows the interrelationships in the communication between the
S7 controller, PN/M-Bus LINK and connected M-Bus devices.
Figure 4-1
Communication paths between S7 controller, PN/M-Bus LINK and M-Bus devices