VLT® 5000/ 5000 FLUX/ 6000 HVAC/
8000 AQUA PROFIBUS
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Profibus DP V1
The Profibus DP extension DP V1 offers additional
to the cyclical data communication an acyclical
communication. This feature can be used by a
DP master type 1 (e.g. PLC), as well as a DP
master type 2 (e.g. PC tool).
Features of a Master type 1 connection
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Cyclical data exchange (DP V0).
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Acyclical read/write on parameters.
The acyclical connection is fixed, and can not
be changed during operation.
Features of a Master type 2 connection:
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Initiate / Abort acyclical connection.
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Acyclical read/write on parameters.
The acyclical connection can dynamically be
established (Initiate) or removed (Abort) even when
a master class 1 is active on the network.
The DP V1 acyclical connection can be used
for general parameter access as an alternative
to the PCV parameter channel.
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Principle of data exchange by Profibus DP V0/DP V1
In a DP cycle the MC 1 will first update the cyclical
process data for all slaves in the system. After that
the MC 1 has the possibility of sending one acyclical
message to one slave. If a MC 2 is connected,
the MC 1 will handle over the Token to MC 2 who
now is aloud to send one acyclical message to one
slave. After that, the token is handled back to the
MC 1, and a new DP cycle is started.
MC1: Master Class 1
MG.90.G1.02 - VLT is a registered Danfoss trademark
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Содержание VLT 5000 Series
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