Danfoss VLT 5042, Руководство по эксплуатации

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VLT® 5000 Crane
Index is used together with the parameter number
for read/write-access to parameters with an index,
such as parameter 615 Error code .
Index has 2 bytes - a lowbyte and a highbyte. However,
only the lowbyte is used. See example below:
Example - index
The first error code (index [1]) in parameter 615
Error code must be read.
PKE = 1267 Hex (read parameter 615 Error code ).
IND = 0001 Hex - Index no. 1.
1267 H 0001 H
PKE IND PWE
The frequency converter will respond in the
parameter value (PWE) block by means of an
error code with a value from 1-99.
Parameter value (PWE)
The parameter value block consists of 2 words
(4 bytes) and its value depends on the command
given (AK). If the master enquires about parameter
value, the PWE block contains no value.
If a parameter value is to be changed by the
master (write), the new value is entered in the
PWE block and sent to the slave.
The transferred text corresponds to the figures given
in the parameter descriptions in the manual. Eg.
parameter 001 Language , where [0] corresponds to
English , and [2] corresponds to French .
However, parameters with data type 9 (text string)
are excepted, as this is transferred as an ASCII text
string. When a text string is transferred (read), the
telegram length is variable, since the texts have different
lengths. The telegram length is stated in the 2nd byte
of the telegram, called LGE. Parameters 621-631
(nameplate data) have data type 9 (text string).
Data types supported by the frequency transformer:
Data types Description
3 Signed 16
4 Signed 32
5 Unsigned 8
6 Unsigned 16
7 Unsigned 32
9 Visible string
10 Byte string
13 Time difference
33 Reserved
35 Bit sequence
Unsigned means that there is no sign included
in the telegram.
Conversion:
The different attributes for each parameter can be seen
in the section on factory settings. Since a parameter
value can only be transferred as a whole number, a
conversion factor must be used to transfer decimals.
Example:
Parameter 202 Output speed high limit has a
conversion factor of 0.1. If you wish to preset the
minimum frequency to 10 Hz, the value 100 must
be transferred, as a conversion factor of 0.1 means
that the value transferred is multiplied by 0.1. The
value 100 will thus be perceived as 10.0. See also
Conversion and Unit of measurement .
Process bytes
The process byte block is divided into two blocks each
of 16 bits, which always come in the sequence stated.
PCD 1 PCD 2
Control telegram
(master
⇒
slave)
Control word Reference-
value
Control telegram
(slave
⇒
master)
Status word Present outp.
frequency
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