Danfoss Metasys N2 Programming Guide

20-22 Setpoint 2
Range: Function:
0
ProcessCtrlUnit*
[-999999.999 -
999999.999
ProcessCtrlUnit]
Setpoint 2 is used in closed-
loop mode to enter a setpoint
reference that may be used
by the frequency converter’s
PID controller. See the
description of
parameter 20-20 Feedback
Function.
NOTICE
The setpoint reference
entered here is added to
any other references that
are enabled (see
parameter group 3-1*
References).
20-23 Setpoint 3
Range: Function:
0
ProcessCtrlUnit*
[-999999.999 -
999999.999
ProcessCtrlUnit]
Setpoint 3 is used in Closed
Loop Mode to enter a
setpoint reference that may
be used by the frequency
converter’s PID Controller. See
the description of
parameter 20-20 Feedback
Function.
NOTICE
The setpoint reference
entered here is added to
any other references that
are enabled (see
parameter group 3-1*).
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 frequency converter’s PID Controller to convert
refrigerant pressure measurements into temperature values.
20-30 Refrigerant
Option: Function:
Select the refrigerant used in the compressor
application. This parameter must be specied
correctly for the pressure to temperature
conversion to be accurate. If the refrigerant
used is not listed in options [0] through [6],
select [7] User dened. Then, use
20-30 Refrigerant
Option: Function:
parameter 20-31 User Dened Refrigerant A1,
parameter 20-32 User Dened Refrigerant A2 and
parameter 20-33 User Dened Refrigerant A3 to
provide A1, A2 and A3 for the equation below:
Temperature = 
A2
ln Pe + 1 − A1
− A3
[0] * R22
[1] R134a
[2] R404A
[3] R407C
[4] R410A
[5] R502
[6] R744
[7] User
dened
20-31 User Dened Refrigerant A1
Range: Function:
10* [8 - 12 ] Use this parameter to enter the value of
coecient A1 when parameter 20-30 Refrigerant is
set to [7] User dened.
20-32 User Dened Refrigerant A2
Range: Function:
-2250* [-3000 -
-1500 ]
Use this parameter to enter the value of
coecient A2 when
parameter 20-30 Refrigerant is set to [7] User
dened.
20-33 User Dened Refrigerant A3
Range: Function:
250* [200 -
300 ]
Use this parameter to enter the value of
coecient A3 when
parameter 20-30 Refrigerant is set to [7] User
dened.
20-34 Duct 1 Area [m2]
Range: Function:
0.500
m2*
[0.001
- 10 m2]
Used for setting the area of the air ducts in
connection with feedback conversion
pressure/velocity to ow. The unit (m
2
) is
determined by the setting of
parameter 0-03 Regional Settings. Fan 1 is used
with feedback 1. In case of
ow dierence
control, set parameter 20-20 Feedback Function
to [1] Dierence, if ow fan 1 – ow fan 2 is to
be controlled.
20-35 Duct 1 Area [in2]
Range: Function:
750
in2*
[1 -
15500
in2]
Used for setting the area of the air ducts in
connection with feedback conversion pressure/
velocity to ow. The unit (in
2
) is determined by
Parameter Descriptions
VLT
®
HVAC Drive FC 102
146 Danfoss A/S © 03/2015 All rights reserved. MG11CE02
33

Danfoss Metasys N2 Specifications

General

Brand	Danfoss
Model	Metasys N2
Category	DC Drives
Language	English