Danfoss VLT FC 100 Series Programming Manual page 145

Parameter Description
20-22 Setpoint 2
Range:
0.000
3 3
ProcessCtrlUnit
NOTE!
The setpoint reference entered here is added to any other
references that are enabled (see parameter group 3-1*).
20-23 Setpoint 3
Range:
0.000
ProcessCtrlUnit
3.18.3 20-3* Feedback Adv. Conversion
In air conditioning compressor applications it is often
useful to control the system based on the temperature of
the refrigerant. However, it is generally more convenient to
directly measure its pressure. This parameter group allows
the adjustable frequency drive's PID controller to convert
refrigerant pressure measurements into temperature
values.
20-30 Refrigerant
Option:
3-118
Function:
[ par. 20-13 - par. Setpoint 2 is used in
20-14 Closed-loop mode to
*
ProcessCtrlUnit] enter a setpoint reference
that may be used by the
adjustable frequency
drive's PID controller. See
the description of
Feedback Function,
20-20 Feedback Function.
Function:
[ par. 20-13 - Setpoint 3 is used in
par. 20-14 Closed-loop Mode to enter
*
ProcessCtrlUnit] a setpoint reference that
may be used by the
adjustable frequency
drive's PID Controller. See
the description of
20-20 Feedback Function.
NOTE!
The setpoint reference
entered here is added
to any other references
that are enabled (see
parameter group 3-1*).
Function:
Select the refrigerant used in the compressor
application. This parameter must be specified
correctly for the pressure to temperature
conversion to be accurate. If the refrigerant
used is not listed in choices [0] through [6],
select User defined [7]. use 20-31 User-defined
MG11CD22 - VLT
®
VLT HVAC Drive Programming Guide
20-30 Refrigerant
Option:
[0] R22
*
[1] R134a
[2] R404a
[3] R407c
[4] R410a
[5] R502
[6] R744
[7] User-
defined
20-31 User-defined Refrigerant A1
Range:
10.0000
20-32 User-defined Refrigerant A2
Range:
-2250.00
20-33 User-defined Refrigerant A3
Range:
250.000
20-34 Duct 1 Area [m2]
Range:
0.500
m2
*
® is a registered Danfoss trademark
Function:
Refrigerant A1, 20-32 User-defined Refrigerant A2
and 20-33 User-defined Refrigerant A3 to provide
A1, A2 and A3 for the equation below:
A 2
Temperature =
( ln ( Pe + 1 ) − A 1 )
Function:
[8.0000 - Use this parameter to enter the
*
12.0000 ] value of coefficient A1 when
20-30 Refrigerant is set to User
defined [7].
Function:
[-3000.00 - Use this parameter to enter the
*
-1500.00 ] value of coefficient A2 when
20-30 Refrigerant is set to User-
defined [7].
Function:
[200.000 - Use this parameter to enter the
*
300.000 ] value of coefficient A3 when
20-30 Refrigerant is set to User-
defined [7].
Function:
[0.001 - Used for setting the area of the air ducts in
10.000 connection with feedback conversion
m2]
pressure/velocity to flow. The unit (m
determined by the setting of 0-03 Regional
Settings. Fan 1 is used with feedback 1. In
case of flow difference control, set
20-20 Feedback Function to [1] Difference, if
flow fan 1 – flow fan 2 is to be controlled.
A 3
−
2 ) is