Fagor DDS, Hardware Manual

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   Installation
INSTAL
LAT
ION
C
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of the
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a
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communica
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8.
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DDS
HARDWARE
Ref.1310
SERCOS ring connection
The SERCOS IEC 1491 interface is an international standard for digital
communications between CNC's and servo drives of CNC machines.
The SERCOS communication ring integrates several functions:
 It carries the velocity command from the CNC to the drive in digital for-
mat with greater accuracy and immunity against outside disturbances.
 It carries the feedback signal from the drive to the CNC.
 It communicates the errors and manages the basic control signals of
the drive (enables).
 It allows setting, monitoring and diagnosis of the parameters from the
CNC with simple and standard procedures.
All this drastically reduces the hardware required at the drive, hence, mak-
ing it more reliable.
Its open standard structure provides compatibility between CNC's and ser-
vo systems from different manufacturers on the same machine.
The different drive modules and the CNC are connected through SERCOS
connector X6 carried by each drive of the FAGOR catalog (see their front
panel) through optic fiber. See chapter
7. CABLES of this manual
It is a ring connection where the 16-position rotary switch (0-15) of each
drive permits selecting the address of each module integrated in it.
Particular
Differentiate each drive with the 16-position rotary switch “NODE SELECT”
with sequential numbers starting from 1.
If the zero identifier is assigned to a drive, that module will be ignored ,
even when the ring stays closed for all purposes for the rest of the drives.
That drive may receive an analog velocity command and be adjusted
through the serial line.
If the drive is going to be identified in the SERCOS ring with a number high-
er than 15, this value cannot be selected using the rotary “NODE SELECT”
switch because it only has 15 positions. Identifying axes in the ring with ad-
dresses higher than 15 requires setting QP13. See this parameter in chap-
ter 13 of the “dds-software” manual.
NOTE. The module must be reset in order for any change made on the
rotary switch to be effective.
INFORMATION. The DRIBUSID parameters of the CNC must have the
same ID numbers as the ones assigned by means of the Node_Select
switch. See figure
F. H8/24
.
If the same motor is to be used as C axis and spindle, the two CNC tables
must have the same value for the DRIBUSID parameter.
i
Example.
For example, a machine has four servo drives identified as 1, 2, 3 and 4.
To ignore the second one, another one must be renamed so they are con-
secutive. The easiest solution for a situation like this will be 1, 0, 3 and 2.
NOTE. Remember that the DRIBUSID parameters of the CNC can also
be modified the same way.
Example.
How to identify an axis addressed in position 24 in the system SERCOS ring?
When the identifier of the axis in the ring is higher than 15 (like in this
case), QP13 must be set so it meets the ratio:
Defined ID = ID to be selected at the rotary (15 x QP13).
Hence, for defined ID = 24 , select the A position at the drive's rotary
“NODE SELECT” switch (same as 9) and set QP13=1.