63
DeviceNet - Design
Inputs:
3 discrete feedback signals from the position measuring system (positions S1 -
S3)
1 discrete feedback signal from the external initiator (S4)
1 analog position signal in mm
supply via DeviceNet string (11 ... 25 V DC)
Switch level high signal ≥ 5 V
Switch level low signal ≤ 1.5 V
Outputs:
3 solenoid valves
Power consumption
from the bus:
max. output 5 W, if all valves are switched (3 x type 6524 with 0.6 W each)
13.3.1
Total line length and maximum line length according to
DeviceNet specification
The bus line is a 4-core cable with additional shielding which must conform to the DeviceNet specification.
The cable transmits both information (data) and energy (power supply for low-power actuators and sensors).
The maximum total line length (sum of trunk lines and drop lines) of a network depends on the baud
rate.
When designing the system, the
calculated line length of the cable at the control head must be
1 m
- this takes into account the outer and inner cable lengths.
Baud rate
Maximum total line length*
Thick Cable**
Mid Cable**
Thin Cable**
125 kBit/s
500 m
300 m
100 m for all baud rates
250 kBit/s
250 m
250 m
500 kBit/s
100 m
100 m
*
According to DeviceNet specification. If a different cable type is used, lower maximum values apply.
**
For cable designation and details - see DeviceNet specification.
13.3.2
Drop line length
Baud rate
Length of the drop lines
Maximum length
Maximum total length of all drop lines in the network
125
kBit/s
6 m for all baud rates
156 m
250
kBit/s
78 m
500
kBit/s
39 m
english
Control Head Type 8681
Summary of Contents for 8681
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