·98·
Installation manual
CNC 8055
CNC 8055i
2.
CNC 8055 I CONFIGURATION
SOFT: V02.2X
CNC structure
DIGITAL DRIVES - Digital servo (CAN or Sercos)
Two types of digital servo systems may be used to communicate with Fagor servo drives:
• Sercos interface IEC1491.
• CAN field bus and standard CanOpen communication protocol. Their characteristics, in general,
are similar to those of a Sercos ring with lower transmission speed.
A system may have digital axes (CAN or Sercos) and analog axes together. On the other hand, it
is not possible to have digital axes with Sercos interface and CAN interface at the same time.
Digital CAN servo
Module identification at the bus.
Each one of the elements integrated into the CAN bus is identified by the 16-position rotary switch
(0-15) "Address" (also referred to as "Node_Select"). This rotary switch selects the address (node)
occupied by each element integrated in the bus.
Although the switch has 16 positions, only positions 1 through 8 are valid. The CNC does not have
a switch, The drives occupy consecutive positions (recommended) starting from ·1·.
The corresponding drive must be turned off and back on (or press the Reset button) for the address
change to be assumed.
The "Line_Term" switch.
The "Line_Term" switch identifies which are the elements that occupy the ends of the CAN bus; i.e.
the first and last physical element in the connection.
The central unit must always be at one end of the line. The other end will be the last one of the remote
module groups.
The switch of the elements at the ends must be in the "1" position and the rest of the elements in
the "0" position. The CNC does not have a switch and always has the terminating resistor activated.
Characteristics of the CAN cable.
Use a specific CAN cable. The ends of all the wires and the shield must be protected by the
corresponding terminal (pin). Also use the terminals (pins) to secure the cable to the connector.
Type: Shielded. Twisted pairs (1 x 2 x 0,22 mm
2
).
Flexibility: Extremely flexible. Minimum bending radius, static = 50 mm and dynamic
= 95 mm.
Cover: PUR.
Impedance: Cat.5 (100 - 120 ).
Although both CAN buses are independent, the CAN addresses of the drives cannot be the same as
the CAN addresses of the I/O modules. If address ·1· is used at the drive's CAN bus, there cannot
be any module with that address in the CAN bus of the I/O's.