Fagor CNC 8070, Hardware Configuration

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Hardware configuration.
CNC 8070
6.
CEN
T
RAL UNIT + MONITOR (Q7-A
PLATFORM).
Conn
ecti
ons.
·136·
(R
EF
: 1911)
Data exchange via Sercos.
The data exchange between the CNC and the drives takes place at every position loop. The
more data is exchanged, the more overloaded the Sercos transmission will be. These
registers should be limited leaving only the ones absolutely necessary after the setup.
There is data that must necessarily be transmitted in every position loop (velocity commands,
feedback, etc.) and other data that may be transmitted in several loops (monitoring, etc.).
Since the CNC must know the priority of those transmissions, there must be two separate
transmission channels.
Cyclic channel (fast).
The data is transmitted in every position loop. It contains the commands, feedback, etc. Each
variable read or written at the drive is included in this information package. In order not to
overload the interface, you must limit the number of drive variables involved to the minimum
necessary.
Indicate the type of data to be transmitted. The data to be sent to the drives must be placed
in certain particular registers of the PLC and the data to be read from the drives is received
in other registers of the PLC.
Service channel (slow).
The data is transmitted in several position loops. It contains monitoring data, etc.
This channel can only be accessed through high-level blocks in the part-program or from
the PLC channel.