Danfoss VLT FC 103, Руководство по программированию

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6-50 Terminal 42 Output
Option: Function:
[141] Bus ctrl t.o. 0-100%, (0-20 mA)
[142] Bus ctrl t.o. 4-20mA 0-100%
[143] Ext. CL 1 4-20mA 0-100%
[144] Ext. CL 2 4-20mA 0-100%
[145] Ext. CL 3 4-20mA 0-100%
[150] Max Out Fr 4-20 mA
NOTE
Values for setting the Minimum Reference is found in open
loop
3-02 Minimum Reference and for closed loop
20-13 Minimum Reference/Feedb. - values for maximum
reference for open loop is found in 3-03 Maximum
Reference and for closed loop 20-14 Maximum Reference/
Feedb. .
6-51 Terminal 42 Output Min Scale
Range: Function:
0 %
*
[0 - 200
%] Scale for the minimum output (0 or 4 mA) of
the analog signal at terminal 42.
Set the value to be the percentage of the full
range of the variable selected in
6-50 Terminal 42 Output .
6-52 Terminal 42 Output Max Scale
Range: Function:
100
%
*
[0 -
200
%] Scale for the maximum output (20mA) of the
analog signal at terminal 42.
Set the value to be the percentage of the full
range of the variable selected in
6-50 Terminal 42
Output .
130BA075.12
(mA)
0%
20
0/4
100%
Current
Analogue
output
Min Scale
par. 6-93 Variable
for
output
example:
Speed
(RPM) Analogue
Output
Max Scale
par. 6-94
Illustration 3.27
It is possible to get a value lower than 20mA at
full scale by programming values >100% by using
a formula as follows:
20 mA / desired maximum current × 100 %
i.e. 10mA : 20 mA
10 mA × 100 % = 200 %
EXAMPLE 1:
Variable value= OUTPUT FREQUENCY, range = 0-100 Hz
Range needed for output = 0-50 Hz
Output signal 0 or 4mA is needed at 0 Hz (0% of range) -
set
6-51 Terminal 42 Output Min Scale to 0%
Output signal 20 mA is needed at 50 Hz (50% of range) -
set
6-52 Terminal 42 Output Max Scale to 50%
0/4 mA
20 mA
50% 100% 0%
50Hz 100Hz 0Hz
130BA858.10
Illustration 3.28
EXAMPLE 2:
Variable= FEEDBACK, range= -200% to +200%
Range needed for output= 0-100%
Output signal 0 or 4 mA is needed at 0% (50% of range) -
set
6-51 Terminal 42 Output Min Scale to 50%
Output signal 20 mA is needed at 100% (75% of range) -
set
6-52 Terminal 42 Output Max Scale to 75%
0/4 mA
20 mA
50% 75% 100% 0%
0% +100% +200% -200%
130BA856.10
Illustration 3.29
EXAMPLE 3:
Variable value= REFERENCE, range= Min ref - Max ref
Range needed for output= Min ref (0%) - Max ref (100%),
0-10 mA
Output signal 0 or 4 mA is needed at Min ref - set
6-51 Terminal 42 Output Min Scale to 0%
Output signal 10 mA is needed at Max ref (100% of range)
- set
6-52 Terminal 42 Output Max Scale to 200%
(20 mA/10 mA x 100%=200%).
Parameter Description
VLT
®
Refrigeration Drive Programming Guide
76 MG16H102 - VLT
®
is a registered Danfoss trademark
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