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Introduction
The following table lists the performance indicators:
Item
Specifications
Communication protocol
EtherCAT
Service supported
CoE (PDO
,
SDO)
Minimum synchronization period of
6-axis cam
2000 us
Synchronization mode
The servo uses a DC-distributed clock. I/O uses I/O synchronization.
Physical layer
100BASE-TX
Baud rate
100 Mbit/s (100Base-TX)
Duplex mode
Full duplex
Topological structure
Cyclic topological structure
Transmission medium
Network cable
Transmission distance
Less than 100 M between two nodes
Number of slaves
65535
EtherCAT frame length
44 bytes to 1498 bytes
Process data
A single Ethernet frame contains a maximum of 1486 bytes.
Synchronization jitter of two slaves
< 1 μs
Refresh time
1000 digital inputs and outputs: approximately 30 us; 32 servo axes:
approximately 100 us
2 Wiring
■
Making network cables
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Figure 5-20
EtherCAT network cable requirements
■
Signal lead arrangement
Pin
Signal
Signal Direction
Signal Description
1
TD+
Output
Data transm
2
TD-
Output
Data transmission -
3
RD+
Input
Data rec
4
--
--
Not in use
5
--
--
Not in use
6
RD-
Input
Data reception -
7
--
--
Not in use
8
--
--
Not in use
■
Length requirement
The FastEthernet technology has proved that the cable length between devices cannot exceed
100 m when the EtherCAT bus is used. Otherwise
,
signal attenuation occurs
,
adversely affecting
communication.
