Danfoss VLT Refrigeration Drive FC 103 Programming Manual page 192

Parameter Description
3.22.4 28-8* P0 Optimization
®
VLT Refrigeration Drive FC 103 supports the VLT
Refrigeration Drive P0 Optimization feature. This enables
automatic adaptation of the suction pressure to match the
3 3
actual load on the system.
To enable this function, set parameter 20-25 Setpoint Type
to [2] Floating. The frequency converter now accepts
setpoint changes from the LON bus. The frequency
converter ensures the minimum and maximum limits for
the feedback suction pressure.
28-81 dP0 Offset
Range:
-999999.9 -
999999.9 []
28-82 P0
Range:
-999999.999 -
999999.999
28-83 P0 Setpoint
Range:
-999999.999 -
999999.999
28-84 P0 Reference
Range:
-999999.999 -
999999.999
28-85 P0 Minimum Reference
Range:
-999999 - [] The largest negative offset value that can be
999999
190
VLT
Function:
The value of the parameter is added to the
setpoint if parameter 20-25 Setpoint Type is set
to [2] Floating. The unit of the parameter is
shown as °K. The feedback is expected to be a
pressure converted to an equivalent
temperature via the pressure-to-temperature
conversion functions available in
parameter 20-01 Feedback 1 Conversion,
parameter 20-03 Feedback 2 Source, or
parameter 20-06 Feedback 3 Source.
Function:
[] The feedback pressure measured on the
analog inputs, converted to an
equivalent temperature.
Function:
[] The setpoint of the frequency converter
excluding any offset in
parameter 28-81 dP0 Offset.
Function:
[] The sum of the setpoint of the frequency
converter (parameter 28-83 P0 Setpoint)
and the offset in parameter 28-81 dP0
Offset.
Function:
entered in parameter 28-81 dP0 Offset without
exceeding the minimum reference value in
parameter 3-02 Minimum Reference. The value is
rounded to the nearest larger integer. If a
numerically larger value is entered, the sum of
the offset and the setpoint is clipped to the
value of parameter 3-02 Minimum Reference.
Danfoss A/S © 05/2016 All rights reserved.
®
Refrigeration Drive FC 103
28-86 P0 Maximum Reference
Range:
®
-999999 -
999999
28-87 Most Loaded Controller
Shows the number of the controller that is loaded the most.
Range:
0
*
3.22.5 28-9* Injection Control
The injection on/off signal is a forced close signal for the
case controllers (controllers that turn display cases off). The
signal is distributed by the following means: Hard-wired
through a digital output/relay or soft-wired via fieldbus by
gateway or system manager.
28-90 injection_on
Range:
0 [0 - 1] Sends the injection on/off signal over the LON bus.
*
28-91 Delayed Compressor Start
Range:
0 [0 -
*
1]
Function:
[] The largest positive offset value that can be
entered in parameter 28-81 dP0 Offset without
exceeding the maximum reference value in
parameter 3-03 Maximum Reference. The value is
rounded to the nearest smaller integer. If a
numerically larger value is entered, the sum of
the offset and the setpoint is clipped to the
value of parameter 3-03 Maximum Reference.
Function:
[0 - 120]
Function:
Value 0 stands for injection OFF, value 1 stands for
injection ON.
Function:
If this parameter is set to 1, the injection control
feature controls the delayed start of the compressor
using parameter 1-71 Start Delay. If this parameter is
set to 0, only parameter 1-71 Start Delay controls the
delayed start of the compressor. If
parameter 28-91 Delayed Compressor Start is set to 1
and injection is OFF, the start of the compressor is
delayed by the time set in parameter 1-71 Start Delay.
If parameter 28-91 Delayed Compressor Start is set to 1
and injection is ON, the start of the compressor is
not delayed. If parameter 28-91 Delayed Compressor
Start is set to 0, the injection controller feature does
not affect the delayed start of the compressor.
Delayed start of the compressor is not active during
the short cycle protection.
MG16H202