Danfoss VLT 6000 HVAC Profibus, Manual

Page: 112 / 177

VLT
®
6000 HVAC
112
★
= factory setting. ( ) = display text [ ] = value for use in communication via serial communication port
MG.60.B1.02 - VLT is a registered Danfoss trade mark
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Feedback signals in open loop
Normally, feedback signals and thus feedback
parameters are only used in Closed loop operation; in
VLT 6000 HVAC units, however, the feedback
parameters are also active in Open loop operation.
In Open loop mode , the feedback parameters can be
used to show a process value in the display. If the
present temperature is to be displayed, the
temperature range can be scaled in parameters 413/
414 Minimum/Maximum feedbac k, and the unit (°C,
°F) in parameter 415 Process units .
413 Minimum feedback, FB
MIN
(MIN. FEEDBACK)
Value:
-999,999.999 - FB
MAX
★
0.000
Function:
Parameters 413 Minimum feedback, FB
MIN
and 414
Maximum feedback, FB
MAX
are used to scale the
display indication, thereby ensuring that it shows the
feedback signal in a process unit proportionally to the
signal at the input.
Description of choice:
Set the value to be shown on the display at minimum
feedback signal value (par. 309, 312, 315 Min.
scaling ) on the selected feedback input (parameters
308/311/314 Analogue inputs ).
414 Maximum feedback, FB
MAX
(MAX. FEEDBACK)
Value:
FB
MIN
- 999,999.999
★
100.000
Function:
See the description of par. 413 Minimum feedback,
FB
MIN
.
Description of choice:
Set the value to be shown on the display when
maximum feedback (par. 310, 313, 316 Max. scaling )
has been achieved at the selected feedback input
(parameters 308/311/314 Analogue inputs ).
415 Units relating to closed loop
(REF. / FDBK. UNIT)
Value:
No unit [0] °C [21]
★
% [1] GPM [22]
rpm [2] gal/s [23]
ppm [3] gal/min [24]
pulse/s [4] gal/h [25]
l/s [5] lb/s [26]
l/min [6] lb/min [27]
l/h [7] lb/h [28]
kg/s [8] CFM [29]
kg/min [9] ft 3 /s [30]
kg/h [10] ft 3 /min [31]
m 3 /s [11] ft 3 /h [32]
m 3 /min [12] ft/s [33]
m 3 /h [13] in wg [34]
m/s [14] ft wg [35]
mbar [15] PSI [36]
bar [16] lb/in 2 [37]
Pa [17] HP [38]
kPa [18] °F [39]
mVS [19]
kW [20]
Function:
Selection of unit to be shown on the display.
This unit will be used if Reference [unit] [2] or
Feedback [unit] [3] has been selected in one of the
parameters 007-010, as well as in the Display mode.
In Closed loop , the unit is also used as a unit for
Minimum/Maximum reference and Minimum/
Maximum feedback , as well as Setpoint 1 and
Setpoint 2 .
Description of choice:
Select the required unit for the reference/feedback
signal.