
5. DIGITAL SERVO
B–63325EN/03
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Connecting the CNC control unit to servo amplifiers via a high–speed
serial servo bus (FANUC Serial Servo Bus, or FSSB), which uses only
one fiber optics cable, can significantly reduce the amount of cabling in
machine tool electrical sections.
In a system employing the FSSB, the following parameters must be
specified to set axes. (Other parameters must be specified as usual.)
· Parameters No. 1023, 1027, and 1028
· Parameters No. 1080 to 1089 (For a system using 11 or more
controlled axes, parameters No. 1100 to 1109 and 1110 to 1119
must also be specified. Hereafter, the description “parameters No.
1080 to 1089” is assumed to include parameters No. 1100 to 1109
and 1110 to 1119 for any system using 11 or more controlled axes.)
· Parameters No. 1092 to 1097
To specify these parameters, any of the following three methods can be
used:
1. Default setting
Default setting is performed for the axes in the order in which they are
connected to amplifiers. Parameters No. 1023, 1027, 1028, 1080 to
1089, and 1092 to 1097 need not be set and automatic setting is not
performed. Note that some functions cannot be used when default
setting is used.
2. Automatic setting
Parameters No. 1023, 1027, 1028, 1080 to 1089, and 1092 to 1097 are
specified automatically according to the interrelationships between
axes and amplifiers entered on the FSSB setting screen.
3. Manual setting
Enter data directly into parameters No. 1023, 1027, 1028, 1080 to
1089, and 1092 to 1097. Before doing this, take the time to become
fully familiar with the use of the parameters.
In a system employing the FSSB, connection is established between the
CNC and servo amplifiers or pulse modules through a fiber optics cable.
Such servo amplifiers or pulse modules are called slaves. A two–axis
amplifier consists of two slaves while a three–axis amplifier consists of
three slaves. Slaves are assigned a number (slave number) from 1 to 10,
where 1 is assigned to the slave nearest to the CNC, 2 to the second
nearest, and so on.
5.2
SETTING THE FSSB
Overview
Description
D Slave