Danfoss AK-PC 781A, User Manual, Page: 55 / 138

AK-PC 781A Capacity controller RS8HE202 © Danfoss 2017-07 55
Set plant type
1. Go to Configuration menu
2. Select plant type
Press the line Select plant type.
3. Set plant type
4. Set Common functions
Press the +-button to go on to the
next page
5. Quick basis setup
Configuration - continued
Adjust only the two lines with "Easy"
(Only when the refrigerant selected is CO2)
Here you can adjust the overall values for the
system
- Regulation Pgc max
- Regulation Receiver reference.
The controller will then suggest values for all
settings connected with this.
Fine adjustments can be made if necessary.
3 - Plant type
Application selection
Select between "One Suction", "One condens-
er" or both "One Pack"
4- Plant type continued
Quick setup
A choice will give a number of predefined com-
binations, which at the same time determine
the connection points.
At the end of the manual there is an overview
of the options and connection points.
After configuration of this function, the
controller will shut down and restart. After the
restart, a large number of settings will have
been made. These include the connection
points. Continue with the settings and check
the values.
If you change some of the settings, the new
values will come into force.
Refrigerant
Select refrigerant type
Refrigerant factors K1, K2, K3
Only used if “Po refrigerant type” is set to custom
(contact Danfoss for information)
Pack type
MT = Medium temperature. LT = Low tempera-
ture. IT = Parallel compression
HP control
High pressure control enabled. To be adjusted
later on.
Receiver control
Receiver control enabled. To be adjusted later
on.
IT Compressor
Parallel compressor (there are special settings;
see the section on page 120).
Heat recovery
Heat recovery enabled. To be adjusted later on.
Oil management
Oil control enabled. To be adjusted later on.
Show advanced settings
This function opens the advanced settings in
the various menus.
Show Tc
If selecting "yes" the Pc pressure will also be
shown as temperature.
External main switch
A switch may be connected for starting and
stopping the regulation. (Also opens UPS
selection)
Mon. Ext. Power loss (signal from an UPS)
Monitoring of external voltage. When selecting
"yes", a digital input is allocated.
Alarm output
Here you may set whether or not it should be
an alarm relay, and which priorities will activate
it.
I'm alive relay
A relay will "release" if the regulation is stop-
ped.
Comp. cap. out to AO
If selecting "yes" indicate the current capacity
of an output.
5 – Quick relative setup
Easy Pgc max. provides a group setting for the
overall pressure values.
Easy Prec ref. provides a group setting for the
receiver controller..
General
If you want to know more about the different configuration options, they are listed in the right column.
The number refers to the number and picture in the column on the left.
As the screen only shows the settings and readings that are required for a given setup, all possible settings
have also been included in the right column.
Our example
The comments for the example are shown on the
following pages, in the middle column.
In our example we want the controller to
control both a compressor group and a
condenser group. We therefore select the
plant type One pack.
Subsequent options are then available,
but only those options allowed by the
current selection.
This setting is special.
Here the user can select a pre-defined
system. We do not use this function in
our example, but perform the adjust-
ments individually.
Select the refrigerant type, here CO2,
further options are made available, etc.
In our example, the cooling (MT) is
regulated.
(If it was a cascade control/two step
system, the other controller would need
to be set to "LP".)
The settings for our example can be
viewed in the display.