Danfoss VLT Decentral FCD 300, Руководство пользователя

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Decentral Solutions
It is possible to change the direction of rotation via the
serial reference. This is done by converting the binary
reference value to 2 ’ complement. See example.
Example - Control word and serial communication ref.:
The variable frequency drive is to receive a start
command and the reference is to be set to 50%
(2000 Hex) of the reference range.
Control word = 047F Hex Start command.
Reference = 2000 Hex 50% reference.
The variable frequency drive is to receive a start
command and the reference is to be set to -50%
(-2000 Hex) of the reference range.
The reference value is first converted to 1 ’ complement,
and then 1 is added binarily to obtain 2 ’ complement:
2000 Hex 0010 0000 0000 0000 0000
1 ’ complement 1101 1111 1111 1111 1111
+ 1
2 ’ complement 1110 0000 0000 0000 0000
Control word = 047F Hex Start command.
Reference = E000 Hex -50% reference.
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Present output frequency
The value of the variable frequency drive ’ s
present output frequency is transferred as a
16-bit word. The value is transferred as whole
numbers 0 - ±32767 (±200%).
16384 (4000 Hex) corresponds to 100%.
Output frequency has the following format:
0-16384 (4000 Hex) 0-100% (Par. 201
Output frequency low limit - Par. 202 Output
frequency high limit ).
Example - Status word and current output frequency:
The master receives a status message from the variable
frequency drive that the current output frequency
is 50% of the output frequency range.
Par. 201 Output frequency low limit = 0 Hz
Par. 202 Output frequency high limit = 50 Hz
Status word = 0F03 Hex.
Output frequency= 2000 Hex 50% of the frequency
range, corresponding to 25 Hz.
MG.90.F2.22 - VLT is a registered Danfoss trademark
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