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Assembly
confocalDT 24x1
Depending on these conditions, the maximum number of controllers to be synchronized
resp. the permitted total cable length can be determined graphically for synchronization
1
100
200
300
400
500
600
700
800
2
3
4
5
6
7
8
9
10 11 12 13 14 15 16 17 18 19 20
Number of slaves
Total cable length [m]
f = 100 Hz ... 10 kHz
f = 25 kHz
f = 50 kHz
f = 70 kHz
Fig. 13 Influence of the measuring rate on synchronization
Star synchronization
Cascaded synchronization
Example: measuring rate = 25 kHz, number of slaves = 13
Solution: total cable length = 170 m,
Partial cable length
between master and slaves
appr. 13 meter (170 m div. 13 slaves)
Partial cable length
between the individual controllers
appr. 2.3 meter (30 m div. 13 slaves)
General
:
N =
CL [nF] + L [m] * 0.1 [nF/m]
C [nF]
max.
In
N
CL
max.
L
C
In
Number of slaves,
Max. permissible load capacitance,
Total cable length,
Input capacity slave (typ. 1 nF)
i
If the controller are operated via the EtherCAT interface, then a synchronization
even without the sync cable can be realized.
