Burkert 8681 - Total Line Length And Maximum Line Length According To Devicenet Specification; Drop Line Length

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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 specication
Thebuslineisa4-corecablewithadditionalshieldingwhichmustconformtotheDeviceNetspecication.
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 specication. If a dierent cable type is used, lower maximum values apply.
** For cable designation and details - see DeviceNet specication.
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