Danfoss VLT 6000 HVAC Profibus, Руководство пользователя

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VLT
®
6000 HVAC
MG.60.B1.02 - VLT is a registered Danfoss trademark
130
Example - control word and
serial communication ref.:
The VLT frequency converter must 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
047F H 2000 H
The VLT frequency converter 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 the first
complement; then 1 binary is added to get 2's
complement:
2000 Hex = 0010 0000 0000 0000 binary
1´ komplement = 1101 1111 1111 1111 binary
+ 1 binary
2´ komplement = 1110 0000 0000 0000 binary
Control word = 047F Hex. Start command
Reference = E000 Hex. -50 % reference
047F H E000 H
Reference
Bit 12, No function:
Bit 12 has no function.
Bit 13, Voltage warning high/low:
Bit 13 = "0" means that there is no voltage warning.
Bit 13 = "1" means that the DC voltage of the VLT
6000 HVAC intermediate circuit is too low or too high.
See the voltage limits on page 151.
Bit 14, Current limit:
Bit 14 = "0" means that the output current is smaller
than the value in parameter 215 Current limit I
LIM
.
Bit 14 = "1" means that the output current is higher
than the value in parameter 215 Current limit I
LIM
and
the VLT frequency converter will trip after the time set
in parameter 412 Trip delay overcurrent, I
LIM
has
passed.
Bit 15, Thermal warning:
Bit 15 = "0" means there is no thermal warning.
Bit 15 = "1" means that the temperature limit has
been exceeded either in the motor, in the VLT
frequency converter or from a thermistor connected
to an analogue input.
■ ■
■ ■ ■
Serial communication reference
Master
➝
Slave
15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 Bit no.
The serial communication reference is transmitted to
the frequency converter in the form of a 16-bit word.
The value is transmitted as whole numbers
0 - ±32767 (±200 %).
16384 (4000 Hex) corresponds to 100 %.
The serial communication reference has the following
format:
0-16384 (4000 Hex) - 0-100 % (par. 204 Minimum
ref. - Par. 205 Maximum ref. ).
It is possible to change the direction of rotation via
the serial reference. This is done by converting the
binary reference value to 2's complement.
See example.
Reference
Control word
Serial com. ref. Control
word
Control word