Eaton PowerXL DX-NET-SWD, Manual

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4 Commissioning
4.4 Acyclic data
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DX-NET-SWD 06/13 MN04012009Z-EN www.eaton.com
4.4 Acyclic data
For normal variable frequency drive operation the acyclic data is not required.
This section therefore addresses programming experts.
4.4.1 Introduction
Acyclic communications are used to read or write parameters and diagnos-
tics in the DC1 variable frequency drive; they can take place at the same time
as cyclic data is being transferred. This means that acyclic communications
are independent from the selected profile.
In this case, the SmartWire-DT coordinator (client) communicates with the
DC1 variable frequency drive acyclic. The communication is always initiated
by the client in the process.
4.4.2 Data Types
Several data types are defined for using the PROFIdrive communication.
The data types used here are specified in the following.
4.4.2.1 PROFIdrive specific
N2 – normalized value
N2 = normalized value for a relative scaling. N2 is in the range of -200 % to
+200 %. 0 % is equivalent to 0 (0x0), 100 % is equivalent to 212 (0x4000).
The representation is carried out in two complements, the most significant
bit (MSN) is the first bit after the unsigned bit (SN) of the first octet.
SN = 0; positive value with 0; SN = 1; negative numbers
Conversion
￫
In order for acyclic data to be transmitted and diagnostic activi-
ties to be performed, the higher-level PLC must feature acyclic
services.
The programmable EASY802-DC-SWD and EASY806-DC-SWD
switchgear and controlgear do not feature acyclic services!
Coding Value Range Resolution Length
113 -200 % ≦ i ≦ (200-2-
14
) % 2-
14
≙ 0.0061 % 2 octets
unsigned bit (bit 15) bit with sign (bit 15)
0
dec
= 0x0000
hex
= 0 %
1
dec
= 0x0001
hex
= 0.0061 % -1
dec
= 0xFFFF
hex
= -0.0061 %
16384
dec
= 0x4000
hex
= 100 % -16384
dec
= 0xC000
hex
= -100 %
32767
dec
= 0x7FFF
hex
= 199.99 % -32768
dec
= 0x8000
hex
= -200 %