Danfoss AK-PC 782A User guide

User Guide

Pack controller

Type AK-PC 782A

Capacity controller for transcritical CO2 booster control

SW Ver. 3.5x

www.danfoss.com

User Guide | Pack controller, type AK-PC 782A

Contents

1.	Introduction.............................................................................			3
	1.1	Application...........................................................................................		3
	1.2	Principles...............................................................................................		4
2. Design of a controller..............................................................				7
	2.1	Module survey.....................................................................................		7
	2.2	Common data for modules..........................................................		10
	2.3	Controller...........................................................................................		11
		2.3.1	Extension module AK-XM 101A...................................	13
		2.3.2	Extension module AK-XM 102A / AK-XM 102B.......	15
		2.3.3	Extension module AK-XM 103A...................................	17
		2.3.4	Extension module AK-XM 204A / AK-XM 204B.......	19
		2.3.5	Extension module AK-XM 205A / AK-XM 205B.......	21
		2.3.6	Extension module AK-XM 208C...................................	23
		2.3.7	Extension module AK-OB 110.......................................	25
		2.3.8	Extension module EKA 163B / EKA 164B..................	26
		2.3.9	Graphic display MMIGRS2..............................................	26
		2.3.10	Power supply module AK-PS 075 / 150 / 250..........	27
		2.3.11 Communication module AK-CM 102.........................		28
	2.4	Preface to design.............................................................................		29
	2.5	Design of a compressor and condenser control..................		31
	2.6	Ordering.............................................................................................		39
3.	Mounting and wiring.............................................................			40
	3.1	Mounting...........................................................................................		40
	3.2	Wiring	..................................................................................................	42
4.	Configuration and operation................................................			45
	4.1	Configuration....................................................................................		45
		4.1.1	Connect PC..........................................................................	45
		4.1.2	Authorization......................................................................	47
		4.1.3	Unlock the configuration of the controllers............	48
		4.1.4	System set-up.....................................................................	49
		4.1.5	Set plant type.....................................................................	50
		4.1.6	Set control of suction group MT..................................	51
		4.1.7	Set oil management.........................................................	55
		4.1.8	Set up control of condenser fans.................................	56
		4.1.9	Set-up of high pressure control...................................	58
		4.1.10	Set up control of receiver pressure.............................	59
		4.1.11 Set-up Receiver Reference with
			Low Pressure Multi Ejectors ..........................................	62
		4.1.12 Set up control of heat recovery....................................		63
		4.1.13 Set up KPI and COP calculation....................................		65
		4.1.14 Set up Display.....................................................................		66
		4.1.15 Set-up Functions for General purpose......................		67
		4.1.16 Separate thermostats......................................................		68
		4.1.17 Separate pressostats........................................................		68
		4.1.18 Separate voltage signals.................................................		69
		4.1.19 Separate alarm inputs......................................................		69

	4.1.20	Separate PI functions.......................................................	70
	4.1.21	Configuration of inputs and outputs.........................	71
	4.1.22	Set alarm priorities............................................................	73
	4.1.23	Lock configuration............................................................	74
	4.1.24 Check configuration.........................................................		75
4.2	Check of connections....................................................................		77
4.3	Check of settings.............................................................................		79
4.4	Schedule function...........................................................................		81
4.5	Installation in network..................................................................		82
4.6	First start of control........................................................................		83
	4.6.1	Start the control.................................................................	84
	4.6.2	Manual capacity control.................................................	85
5. Regulating functions.............................................................			86
5.1	Suction group...................................................................................		86
5.2	Capacity control of compressors...............................................		87
	5.2.1	Capacity distribution methods.....................................	89
	5.2.2	Power pack types – compressor combinations......	90
	5.2.3	Compressor timers............................................................	94
	5.2.4	Compressor with variable capacity.............................	94
	5.2.5	Load shedding....................................................................	96
	5.2.6	Injection ON........................................................................	96
	5.2.7	Liquid injection in common suction line..................	97
	5.2.8	Safety functions.................................................................	98
5.3	Oil management............................................................................		100
5.4	Condenser / Gas cooler...............................................................		102
	5.4.1	Capacity control of condenser...................................	102
	5.4.2	Reference for gas cooler temperature.....................	102
	5.4.3	Capacity distribution......................................................	104
5.5	Condenser couplings...................................................................		105
5.6	Safety functions for condenser................................................		105
5.7	CO2 transcritical system and heat recovery.........................		106
	5.7.1	Circuit for heat recovery or hot tap water..............	107
	5.7.2	Circuit for recovery for heating..................................	108
	5.7.3	Circuits for control of CO2 gas pressure...................	112
	5.7.4	Ejector control..................................................................	114
	5.7.5	Receiver control...............................................................	118
	5.7.6	Safety procedures ..........................................................	119
	5.7.7	Actions on low receiver pressure ..............................	120
	5.7.8	Parallel Compression .....................................................	121
5.8	Setpoint Management................................................................		125
5.9	General monitoring functions..................................................		129
5.10	Miscellaneous.................................................................................		131
5.11	KPI and COP calculations............................................................		136
5.12	Appendix A –
	Compressor combinations and coupling patterns...........		138
5.13	Appendix B – Alarm texts...........................................................		144

2 | BC245386497365en-000801

© Danfoss | Climate Solutions | 2022.02

User Guide | Pack controller, type AK-PC 782A

1. Introduction

1.1 Application

AK-PC 782A are complete regulating units for capacity control of compressors and condensers in a transcritical CO2 booster system with parallel compressor. The controller is with oil management, heat recovery function and CO2 gas pressure control.

In addition to capacity control, the controllers can give signals to other controllers about the operating condition, e.g. forced closing of expansion valves, alarm signals and alarm messages.

The controller’s main function is to control compressors and condensers so that operation all the time takes place at the energy-optimum pressure conditions. Both suction pressure and condensing pressure are controlled by signals from pressure transmitters.

Capacity control must be carried out by suction pressure P0. (The P0 signal for the parallel compressor is supplied by the pressure transmitter on the receiver).

Among the different functions are:

•Capacity control of up to 10 compressors on MT and 8 on IT

•Capacity control of up to 4 compressors on LT

•Up to 3 unloaders for each compressor

•Control of oil separator and oil receiver

•Speed control of one or two compressors in each group

•Up to 6 safety inputs for each compressor

•Option for capacity limitation to minimize consumption peaks

•If the compressor does not start, signals can be transmitted to other controllers so that the electronic expansion valves will be closed

•Regulation of liquid injection into suction line

•Safety monitoring of high pressure / low pressure / discharge temperature

•Capacity control of up to 8 fans

•Floating reference with regard to outside temperature

•Heat recovery function

•CO2 gas cooler control and receiver control

•Ejector regulation: HP, LE (liquid)

•Safety monitoring of fans

•The status of the outputs and inputs is shown by means of lightemitting diodes on the front panel

•Alarm signals can be generated via data communication

•Alarms are shown with texts so that the cause of the alarm is easy to see.

•Plus some completely separate functions that are totally independent of the regulation – such as alarm, thermostat, pressure and PI-regulating functions.

SW = 3.5x

Examples

Traditional capacity control

Prec

Heat recovery functions, controlling the condensing pressure and receiver pressure

© Danfoss | Climate Solutions | 2022.02

BC245386497365en-000801 | 3

User Guide | Pack controller, type AK-PC 782A

1.2 Principles

The great advantage of this series of controllers is that it can be extended as the size of the plant is increased. It has been developed for refrigeration control systems, but not for any specific application – variation is created through the read-in software and the way you choose to define the connections. The same modules that are used for each regulation and the composition can be changed, as required. With these modules (building blocks) it is possible to create a multitude of various kinds of regulations. But it is you who must help adjusting the

regulation to the actual needs – these instructions will assist you to find your way through all the questions so that the regulation can be defined and the connections made.

Advantages

•The controller’s size can “grow” as systems grow

•The software can be set for one or more regulations

•Several regulations with the same components

•Extension-friendly when systems' requirements are changed

•Flexible concept:

–Controller series with common construction

–One principle – many regulation uses

–modules are selected for the actual connection requirements

–The same modules are used from regulation to regulation

Controller	Extension modules

Top part

Bottom part

The controller is the cornerstone of the regulation. The module has inputs and outputs capable of handling small systems.

•The bottom part – and hence the terminals – are the same for all controller types.

•The top part contains the intelligence with software. This unit will vary according to controller type. But it will always be supplied together with the bottom part.

•In addition to the software, the top part is provided with connections for data communication and address setting.

If the system grows and more functions have to be controlled, the regulation can be extended.

With extra modules more signals can be received and more relays cut in and out – how many of them – and which – is determined by the relevant application.

Examples	A regulation with few connections
	can be performed with the controller
	module alone.

If there are many connections, one or more extension modules have to be mounted.

4 | BC245386497365en-000801

© Danfoss | Climate Solutions | 2022.02

User Guide | Pack controller, type AK-PC 782A
Direct connection
Setup and operation of an AK controller must be accomplished via
the “AK-Service Tool” software program.
The program is installed on a PC, set up and operation of the
various functions is carried out via the controller’s menu displays.
Displays
The menu displays are dynamic, so that different settings in one
menu will result in different setting possibilities in other menus.
A simple application with few connections will give a set-up with
few settings.
A corresponding application with many connections will give a
set-up with many settings.
From the overview display there is access to further displays for
the compressor regulation and the condenser regulation.
At the bottom of the display there is access to a number of general
functions, such as “time table”, “manual operation”, “log function”,
“alarms”, and “service” (configuration).
Network linking
The controller can be linked up to a network together with other
controllers in an ADAP-KOOL® refrigeration control system. After
the set-up, operation can be performed at a distance with e.g. our
software program type AKM.
Users
The controller comes supplied with several languages, one of
which can be selected and employed by the user. If there are
several users, they may each have their choice of language. All
users must be assigned a user profile which either gives access to
full operation or gradually limits the operation to the lowest level
that only allows you “to see”.
Language selection is part of the Service Tool settings.
If the language selection is not available in the Service Tool for the
current regulator, English texts will be displayed.
External display
An external display can be fitted in order for P0 (Suction) and Pc
(Condensing) readings to be displayed.
A total of 4 displays can be fitted and with one setting it is possible
to choose between the following readings: suction pressure,
suction pressure in temperature, Ss, Sd, condenser pressure,
condenser pressure in temperature, S7 gas cooler temperature,
hot tap water at heat recovery and heat exchanger temperature at
heat recovery.
A graphical display with control buttons can also be fitted.
© Danfoss | Climate Solutions | 2022.02	BC245386497365en-000801 | 5

User Guide | Pack controller, type AK-PC 782A

Light-emitting diodes

A number of light-emitting diodes makes it possible to follow the signals that are received and transmitted by the controller.

Log

From the log function you can define the measurements you wish to be shown.

The collected values can be printed, or you may export them to a file. You can open the file in Excel.

If you are in a service situation, you can show measurements in a trend function. The measurements are then made real-time and displayed instantly.

Alarm

The display gives you an overview of all active alarms. If you wish to confirm that you have seen the alarm you can cross it off in the acknowledge field.

If you want to know more about a current alarm you can click on it and obtain an information display on the screen.

A corresponding display exists for all earlier alarms. Here you can upload information if you need further details about the alarm history.

n Power
n Comm
n DO1	n Status
n DO2	n Service Tool
n DO3	n LON
n DO4	n I/O Extension
n DO5	n Alarm
n DO6
n DO7	n Display
n DO8	n Service Pin

Slow flash = OK

Quick flash = answer from gateway Constantly ON = error

Constantly OFF = error

Flash = active alarm/not cancelled Constant ON = Active alarm/cancelled

6 | BC245386497365en-000801

© Danfoss | Climate Solutions | 2022.02

User Guide | Pack controller, type AK-PC 782A

2. Design of a controller

This section describes how the controller is designed.

The controller in the system is based on a uniform connection platform where any deviations from regulation to regulation is determined by the used top part with a specific software and which input and output signals the relevant application will require. If it is an application with few connections, the controller

2.1 Module survey

Controller module – capable of handling minor plant requirements.

Extension modules

When the complexity becomes greater and additional inputs or outputs are required, modules can be attached to the controller. A plug on the side of the module will transmit the supply voltage and data communication between the modules.

Top part

The upper part of the controller module contains the intelligence. This is the unit where the regulation is defined and where data communication is connected to other controllers in a bigger network.

module (top part with belonging bottom part) may be sufficient. If it is an application with many connections, it will be necessary to use the controller module plus one or more extension modules. This section will give you a survey of possible connections plus assistance in selecting the modules required by your actual application.

Optional connection

When a regulation is planned (set up), it will generate a need for a number of connections distributed on the mentioned types. This connection must then be made on either the controller module or an extension module. The only thing to be observed is that the types must not be mixed (an analogue input signal must for instance not be connected to a digital input).

Programming of connections

The controller must know where you connect the individual input and output signals. This takes place in a later configuration where each individual connection is defined based on the following principle:

• to which module?

Connection types

There are various types of inputs and outputs. One type may, for example, receive signals from sensors and switches. Another may receive a voltage signal, and a third type may be outputs with relays etc. The individual types are shown in the table below.

•at which point (”terminals”)?

•what is connected (e.g. pressure transmitter/type/pressure range)?

© Danfoss | Climate Solutions | 2022.02

BC245386497365en-000801 | 7

User Guide | Pack controller, type AK-PC 782A

Extension module with additional analogue inputs

External display for suction pressure etc.

Bottom part

Controllerwithanalogue inputsandrelayoutputs.

Top part

Extension module with

2x analogue output signals

If the row of modules needs to be interrupted due to length or external positioning, a communication module should be used.

Extension module with additional relay outputs and additional analogue inputs.

The module with additional relay outputs is also available in a version where the top part is provided with change-over switches so that the relays can be overridden.

8 | BC245386497365en-000801

© Danfoss | Climate Solutions | 2022.02

User Guide | Pack controller, type AK-PC 782A

1. Controller

Type	Function	Application
	Controller for capacity control of MT (10 compressors), IT (8 compressors) and	Transcritical CO2 booster control, parallel
AK-PC 782A	LT (4 compressors).	compression / Oil management / Heat recovery
	Up to 3 unloaders per compressor, 8 fans and max. 220 inputs/outputs.	/ CO2 gas pressure

2. Extension modules and survey of inputs and outputs

Type		Analogue	On/Off outputs		On/off supply voltage		Analogue	Stepper	Module with
		inputs			(DI signal)		outputs	output	switches
		For sensors,	Relay	Solid state	Low voltage	High voltage	0 – 10 V DC	For valves	For override of
		pressure	(SPDT)		(max. 80 V)	(max. 260 V)		with step	relay outputs
		transmitters etc.						control
Controller		11	4	4	-	-	-		-
Extension modules
AK-XM 101A		8
AK-XM 102A					8
AK-XM 102B						8
AK-XM 103A		4					4
AK-XM 204A			8
AK-XM 204B			8						x
AK-XM 205A		8	8
AK-XM 205B		8	8						x
AK-XM 208C		8						4
The following extension module can be placed on the PC board in the controller module.
There is only room for one module.
AK-OB 110							2

3. AK operation and accessories

	Type	Function	Application
	Operation
	AK-ST 500	Software for operation of AK controllers	AK-operation
	-	Cable between PC and AK controller	USB A-B (Standard IT cable)
	Accessories	Power supply module 230 V / 115 V to 24 V DC
	AK-PS 075	18 VA
	AK-PS 150	36 VA	Supply for controller
	AK-PS 250	60 VA
	Accessories	External display that can be connected to the controller module. For showing e.g. the suction pressure
	EKA 163B	Display
	EKA 164B	Display with operation buttons
	MMIGRS2	Graphic display with operation
	-	Cable between EKA display and controller	Length = 2 m, 6 m
		Cable between graphic display and controller	Length = 1.5 m, 3.0 m
	Accessories	Communication modules for controllers where modules cannot be connected continuously
	AK-CM 102	Communication module	Data communication for external extension
			modules

On the following pages there is data specific to each module.

© Danfoss | Climate Solutions | 2022.02

BC245386497365en-000801 | 9

User Guide | Pack controller, type AK-PC 782A

2.2 Common data for modules

Supply voltage	24 V DC/AC ±20%
Power consumption	AK-__ (controller)	8 VA
	AK-XM 101, 102, 103, 107, AK-CM 102	2 VA
	AK-XM 204, 205, 208	5 VA
Analogue inputs	Pt 1000 ohm /0 °C	Resolution: 0.1 °C
		Accuracy: ±0.5 °C
		±0.5 °C between -50 °C and 50 °C
		±1 °C between -100 °C and -50 °C
		±1 °C between 50 °C and 130 °C
	Pressure transmitter type AKS 32R / AKS 2050	Resolution:1 mV
	MBS 2050 / AKS 32 (1 – 5 V)	Accuracy +/- 10 mV
		Max. connection of 5 pressure transmitters on one
	Other pressure transmitter:
	Ratiometric signal	module
	Min. and Max. pressure must be set
	Voltage signal 0 – 10 V
	Contact function (On/Off)	On at R < 20 ohm
		Off at R > 2K ohm
		(Gold-plated contacts not necessary)
Analogue outputs	0 – 10 V	Accuracy +/- 100 mV
On/off supply voltage inputs	Low voltage	Off: U < 2 V
	0 / 80 V AC/DC	On: U > 10 V
	High voltage	Off: U < 24 V
	0 / 260 V AC	On: U > 80 V
Relay outputs	AC-1 (ohmic)	4 A
SPDT	AC-15 (inductive)	3 A
	U	Min. 24 V
		Max. 230 V
		Low and high voltage must not be connected to the
		same output group
Solid state outputs	Can be used for loads that are cut in and out	Max. 240 V AC, Min. 48 V AC
	frequently,	Max. 0,5 A,
	e.g. Ejector valves, Oil valves, fans and AKV valves	Leak < 1 mA
		Max. 1 AKV
Stepper outputs	Used for valves with stepper input	20 – 500 step/s
		Separate supply to stepper outputs : 24 AC/DC
Ambient temperature	During transport	-40 – 70 °C
	During operation	-20 – 55 °C ,
		0 – 95% RH (non condensing)
		No shock influences / vibrations
Enclosure	Material	PC / ABS
	Class	IP10, VBG 4
	Mounting	For mounting on panel wall or DIN rail
Weight with screw terminals	Modules in 100- / 200- / controller-series	Ca. 200 g / 500 g / 600 g
Approvals	EU low voltage directive and EMC requirements	LVD tested according to EN 60730
	are complied with	EMC tested
		Immunity according to EN 61000-6-2
		Emission according to EN 61000-6-3
		E31024 for PC-module
		E357029 for XM and CM-modules

The mentioned data applies to all modules.

If data is specific, this is mentioned together with the module in question.

Dimensions
The module dimension is 72 mm.
Modules in the 100-series consist of one
module.
Modules in the 200-series consist of two
modules.
Controllers consist of three modules.
The length of an aggregate unit = n x 72 + 8
10 | BC245386497365en-000801	© Danfoss | Climate Solutions | 2022.02

User Guide | Pack controller, type AK-PC 782A

2.3 Controller

Function

There are several controllers in the series. The function is determined by the programmed software, but on the outside the controllers are identical – they all have the same connection possibilities:

11 analogue inputs for sensors, pressure transmitters, voltage signals and contact signals.

8 digital outputs, with 4 Solid state outputs and 4 relay outputs.

Supply voltage

24 V AC or DC to be connected to the controller.

The 24 V must not be retransmitted and used by other controllers as it is not galvanically separated from inputs and outputs. In other words, you must use a transformer for each controller. Class II is required. The terminals must not be earthed.

The supply voltage to any extension module is transmitted via the plug on the right-hand side.

The size of the transformer is determined by the power requirement of the total number of modules.

The supply voltage to a pressure transmitter can be taken either from the 5 V output or from the 12 V output depending on transmitter type.

Data communication

If the controller is to be included in a system, communication must take place via the LON connection.

The installation has to be made as mentioned in the separate instructions for LON communication.

Address setting

If it is a system manager AK-SM .., then 1-999

Service PIN

When the controller is connected to the data communication cable, the gateway must have knowledge of the new controller. This is obtained by pushing the key PIN. The LED “Status” will flash when the gateway sends an acceptance message.

Operation

The configuration operation of the controller must take place from the software program “Service Tool”. The program must be installed on a PC, and the PC must be connected to the controller via the USB-B plug on the front of the unit.

Light-emitting diodes

There are two rows with LEDs indicating: Left row:

•Voltage supply to the controller

•Communication active with the bottom PC board (red = error)

•Status of outputs DO1 to DO8

Right row:

•Software status (slow flash = OK)

•Communication with Service Tool

•Communication on LON

•Communication with AK-CM 102

•Alarm when LED flashes

– 1 LED that is not used

•Communication with display on RJ11 plug

•“Service Pin” switch has been activated

PIN

Address

Keep the safety distance!

Low and high voltage must not be connected to the same output group

n Power
n Comm
n DO1	n Status
n DO2	n Service Tool
n DO3	n LON
n DO4	n I/O Extension
n DO5	n Alarm
n DO6
n DO7	n Display
n DO8	n Service Pin

Slow flash = OK

Quick flash = answer from gateway Constantly ON = error

Constantly OFF = error

Flash = active alarm/not cancelled Constant ON = Active alarm/cancelled

A small module (option board) can be placed on the bottom part of the controller. The module is described later in the document.

© Danfoss | Climate Solutions | 2022.02

BC245386497365en-000801 | 11

User Guide | Pack controller, type AK-PC 782A

Point

Analogue inputs on 1 - 11

Solid state outputs on 12 - 15

Relay or AKV coil fx 230 V AC

Point	1	2	3	4	5	6	7	8	9	10	11
Type	AI1	AI2	AI3	AI4	AI5	AI6	AI7	AI8	AI9	AI10	AI11

Terminal 15 & 27:

12 V max. 100 mA in total.

Terminal 16 & 28:

5 V max. 100 mA in total.

Terminal

17, 18, 29, 30:

(Cable screen) The screen on the

pressure transmitter cables must only be connected at the end of the controller.

Relay outputs on 16 - 19

	24 and 25 used only
	when "Option board
		Point	12	13	14	15	16	17	18	19
	fitted"
		Type	DO1	DO2	DO3	DO4	DO5	DO6	DO7	DO8

			Signal	Signal type
S			S1
			S2
Pt 1000 ohm/0°C			Saux_
			SsA	Pt 1000
			SdA
			Shr
			Stw
			Sgc
P
AKS 32R	3: Brown
	2: Blue		P0A	AKS 32R /
				AKS 2050
			P0B
	1: Black			MBS 8250
			PcA
				-1 - xx bar
			PcB
			Paux	AKS 32
AKS 32	3: Brown		Pgc
				-1 - zz bar
			Prec
	2: Black
	1: Red
U				0 - 5 V
			...	0 - 10 V
On/Off			Ext.	Active at:
			Main
			switch	Closed
			Day/
				/
			Night
				Open
			Door
			Level
			switch
DO				Active at:
		<![if ! IE]> <![endif]>AKV	AKV	On
			Comp 1	/
			Comp 2	Off
			Fan 1
			Alarm
			Light
			Rail heat
			Defrost
			Solenoid
			valve

Option Board	Please see the signal
	on the page with the
	module.

Signal	Module	Point		Terminal		Signal type /Active at
		1	(AI 1)	1	- 2
		2	(AI 2)	3	- 4
		3	(AI 3)	5	- 6
		4	(AI 4)	7	- 8
		5	(AI 5)	9 - 10
		6	(AI 6)	11	- 12
		7	(AI 7)	13	- 14
		8	(AI 8)	19	- 20
		9	(AI 9)	21	- 22
		10	(AI 10)	23	- 24
	1	11	(AI 11)	25	- 26
		12	(DO 1)	31	- 32
		13	(DO 2)	33	- 34
		14	(DO 3)	35	- 36
		15	(DO 4)	37	- 38
		16	(DO 5)	39 - 4041
		17 (DO6)		42 - 43 - 44
		18 (DO7)		45 - 46 - 47
		19 (DO8)		48 - 49 - 50

24-

25-

12 | BC245386497365en-000801

© Danfoss | Climate Solutions | 2022.02

User Guide | Pack controller, type AK-PC 782A

2.3.1 Extension module AK-XM 101A

Function

The module contains 8 analogue inputs for sensors, pressure transmitters, voltage signals and contact signals.

Supply voltage

The supply voltage to the module comes from the previous module in the row.

Supply voltage to a pressure transmitter can be taken from either the 5 V output or the 12 V output depending on transmitter type.

Light-emitting diodes

Only the two top LEDs are used. They indicate the following:

•Voltage supply to the module

•Communication with the controller is active (red = error)

© Danfoss | Climate Solutions | 2022.02

BC245386497365en-000801 | 13

User Guide | Pack controller, type AK-PC 782A

Point

At the top, the signal input is the left of the two terminals.

At the bottom, the signal input is the right of the two terminals.

		Point			1		2								3	4
		Type			AI1		AI2								AI3	AI4

Terminal 9 & 15:

12 V max. 100 mA in total.

Terminal 10 & 16:

5 V max. 100 mA in total.

Terminal

11, 12, 13, 14: (Cable screen)

The screen on the pressure transmitter cables must only be connected at the end of the controller.

			Signal	Signal
				type
	S		S1
	Pt 1000 ohm/0°C		S2
			Saux	Pt 1000
			SsA
			SdA
			Shr
			Stw
			Sgc
	P
	AKS 32R	3: Brown
		2: Blue	P0A	AKS 32R /
		1: Black	P0B	AKS 2050
			PcA	MBS 8250
			PcB	-1 - xx bar
	AKS 32		Paux
		3: Brown	Pgc	AKS 32
			Prec	-1 - zz bar
		2: Black
		1: Red
	U
			...	0 - 5 V
				0 - 10 V
	On/Off		Ext.	Active at:
			Main
			switch	Closed
			Day/	/
			Night	Open
			Door
			Level
			switch

Point	5	6	7	8
Type	AI5	AI6	AI7	AI8

Signal	Module	Point	Terminal		Signal type /
					Active at
		1 (AI 1)	1	- 2
		2 (AI 2)	3	- 4
		3 (AI 3)	5	- 6
		4 (AI 4)	7	- 8
		5 (AI 5)	17	- 18
		6 (AI 6)	19	- 20
		7 (AI 7)	21	- 22
		8 (AI 8)	23	- 24

14 | BC245386497365en-000801

© Danfoss | Climate Solutions | 2022.02

User Guide | Pack controller, type AK-PC 782A

2.3.2 Extension module AK-XM 102A / AK-XM 102B

Function

The module contains 8 inputs for on/off voltage signals.

Signal

AK-XM 102A is for low voltage signals.

AK-XM 102B is for high voltage signals.

Supply voltage

The supply voltage to the module comes from the previous module in the row.

Light-emitting diodes

They indicate:

•Voltage supply to the module

•Communication with the controller is active (red = error)

•Status of the individual inputs 1 to 8 (when lit = voltage

AK-XM 102A

AK-XM 102B

Max. 24 V

Max. 230 V

On/Off:

On/Off:

On: DI > 10 V AC/DC

On: DI > 80 V AC

Off: DI <   2 V AC/DC

Off: DI < 24 V AC

© Danfoss | Climate Solutions | 2022.02

BC245386497365en-000801 | 15

User Guide | Pack controller, type AK-PC 782A

Point

		Point			1						2		3	4
		Type			DI1							DI2	DI3	DI4

Point	5	6	7	8
Type	DI5	DI6	DI7	DI8

		Signal Active at
	DI	Ext.
		Main
	AK-XM 102A: Max. 24 V	switch
			Closed
	AK-XM 102B: Max. 230 V	Day/
			(voltage on)
		Night
		Comp.	/
		safety 1	Open
		Comp.	(voltage
			off)
		safety 2

Level switch

(The module can not register a pulse signal from e.g. a reset function.)

Signal	Module	Point	Terminal		Active at
		1 (DI 1)	1	- 2
		2 (DI 2)	3	- 4
		3 (DI 3)	5	- 6
		4 (DI 4)	7	- 8
		5 (DI 5)	9 - 10
		6 (DI 6)	11	- 12
		7 (DI 7)	13	- 14
		8 (DI 8)	15	- 16

16 | BC245386497365en-000801

© Danfoss | Climate Solutions | 2022.02

User Guide | Pack controller, type AK-PC 782A

2.3.3 Extension module AK-XM 103A

Function

The module contains :

4 analogue inputs for sensors, pressure transmitters, voltage signals and contact signals.

4 analogue voltage outputs of 0 - 10 V

Supply voltage

The supply voltage to the module comes from the previous module in the row.

Supply voltage to a pressure transmitter can be taken from either the 5 V output or the 12 V output depending on transmitter type.

Galvanic isolation

The inputs are galvanically separated from the outlets.

The outlets AO1 and AO2 are galvanically separated from AO3 and AO4.

Light-emitting diodes

Only the two top LEDs are used. They indicate the following:

•Voltage supply to the module

•Communication with the controller is active (red = error)

Max. load

I < 2.5 mA

R > 4 kΩ

Accuracy

Analog inputs: +/- 10 mV

Analog outputs: +/- 100 mV

© Danfoss | Climate Solutions | 2022.02

BC245386497365en-000801 | 17

User Guide | Pack controller, type AK-PC 782A

Point						Terminal 9:
	Point	1	2	3	4
						12 V max. 100 mA in total.
	Type	AI1	AI2	AI3	AI4

At the top, the signal input is the left of the two terminals.

At the bottom, the signal input is the right of the two terminals.

Terminal 10:

5 V max. 100 mA in total.

Terminal 11, 12: (Cable screen)

The screen on the pressure transmitter cables must only be connected at the end of the controller.

Galvanic isolation:

AI 1-4 ≠ AO 1-2 ≠ AO 3-4

	Signal	Signal	Point	5	6	7	8
			Type	AO1	AO2	AO3	AO4
		type
S	S1
Pt 1000 ohm/0°C	S2
	Saux	Pt 1000
	SsA
	SdA
	Shr
	Stw
	Sgc
P
AKS 32R
3: Brown
2: Blue	P0A	AKS 32R /
		AKS 2050
1: Black	P0B
		MBS 8250
	PcA
		-1 - xx bar
	PcB
AKS 32
	Paux	AKS 32
3: Brown	Pgc
		-1 - zz bar
	Prec
2: Black
1: Red
U			Signal			Module		Point	Terminal	Signal type /Active at
	...	0 - 5 V						1 (AI 1)	1 - 2
		0 - 10 V						2 (AI 2)	3 - 4
								3 (AI 3)	5 - 6
								4 (AI 4)	7 - 8
On/Off	Ext.	Active at:						5 (AO 1)	17 - 18
	Main
	switch	Closed						6 (AO 2)	19 - 20
	Day/
		/
	Night							7 (AO 3)	21 - 22
		Open
	Door							8 (AO 4)	23 - 24
	Level
	switch
AO
		0 – 10 V
18 | BC245386497365en-000801								© Danfoss | Climate Solutions | 2022.02

User Guide | Pack controller, type AK-PC 782A

2.3.4 Extension module AK-XM 204A / AK-XM 204B

Function

The module contains 8 relay outputs.

Supply voltage

The supply voltage to the module comes from the previous module in the row.

AK-XM 204B only

Override of relay

Eight change-over switches at the front make it possible to override the relay’s function.

Either to position OFF or ON.

In position Auto the controller carries out the control.

Light-emitting diodes

There are two rows with LEDs. They indicate the following: Left row:

•Voltage supply to the controller

•Communication active with the bottom PC board (red = error)

•Status of outputs DO1 to DO8

Right row: (AK-XM 204B only):

•Override of relays ON = override OFF = no override

Fuses

Behind the upper part there is a fuse for each output.

AK-XM 204A

AK-XM 204B

Max. 230 V

Keep the safety distance!

AC-1: max. 4 A (ohmic)

Low and high voltage must

AC-15: max. 3 A (Inductive)

not be connected to the

same output group

AK-XM 204B

Override of relay

© Danfoss | Climate Solutions | 2022.02

BC245386497365en-000801 | 19

User Guide | Pack controller, type AK-PC 782A

Point

Point	1	2	3	4	5	6	7	8
Type	DO1	DO2	DO3	DO4	DO5	DO6	DO7	DO8

	Signal	Active at
DO	Comp. 1
	Comp. 2	On
		/
	Fan 1	Off
	Alarm
	Solenoid
	valve

Signal	Module	Point	Terminal	Active at
		1 (DO 1)	25 - 27
		2 (DO 2)	28 - 30
		3 (DO 3)	31 - 33
		4 (DO 4)	34 -36
		5 (DO 5)	37 - 39
		6 (DO 6)	40 - 41 - 42
		7 (DO 7)	43 - 44 - 45
		8 (DO 8)	46 - 47 - 48

20 | BC245386497365en-000801

© Danfoss | Climate Solutions | 2022.02

User Guide | Pack controller, type AK-PC 782A

2.3.5 Extension module AK-XM 205A / AK-XM 205B

Function

The module contains:

8 analogue inputs for sensors, pressure transmitters, voltage signals and contact signals.

8 relay outputs.

Supply voltage

The supply voltage to the module comes from the previous module in the row.

AK-XM 205B only

Override of relay

Eight change-over switches at the front make it possible to override the relay’s function.

Either to position OFF or ON.

In position Auto the controller carries out the control.

Light-emitting diodes

There are two rows with LEDs. They indicate the following: Left row:

•Voltage supply to the controller

•Communication active with the bottom PC board (red = error)

•Status of outputs DO1 to DO8

Right row: (AK-XM 205B only):

•Override of relays

–ON = override

–OFF = no override

Fuses

Behind the upper part there is a fuse for each output.

AK-XM 205A

AK-XM 205B

max. 10 V

Max. 230 V

Keep the safety distance!

AC-1: max. 4 A (ohmic)

Low and high voltage

AC-15: max. 3 A (Inductive)

must not be connected to

the same output group

AK-XM 205B

Override of relay

© Danfoss | Climate Solutions | 2022.02

BC245386497365en-000801 | 21

User Guide | Pack controller, type AK-PC 782A

Point

Point	1	2	3	4	5	6	7	8
Type	AI1	AI2	AI3	AI4	AI5	AI6	AI7	AI8

Terminal 9 & 21:

12 V max. 100 mA in total.

Terminal 10 & 22:

5 V max. 100 mA in total.

Terminal 11, 12, 23, 24 : (Cable screen)

The screen on the pressure transmitter cables must only be connected at the end of the controller.

Point	9	10	11	12	13	14	15	16
Type	DO1	DO2	DO3	DO4	DO5	DO6	DO7	DO8

	Signal	Signal
		type
S	S1
Pt 1000 ohm/0°C	S2
	Saux	Pt 1000
	SsA
	SdA
	Shr
	Stw
	Sgc
P
AKS 32R
3: Brown		AKS 32R /
2: Blue	P0A
		AKS 2050
	P0B
1: Black		MBS 8250
	PcA
		-1 - xx bar
	PcB
AKS 32	Paux	AKS 32
	Pgc
3: Brown		-1 - zz bar
	Prec
2: Black
1: Red		Signal	Module	Point	Terminal	Signal type /Active at
				1 (AI 1)	1 - 2
U				2 (AI 2)	3 - 4
	...	0 - 5 V		3 (AI 3)	5 - 6
		0 - 10 V		4 (AI 4)	7 - 8
On/Off				5 (AI 5)	13 - 14
	Ext. Main			6 (AI 6)	15 - 16
		Active at:
	switch
	Day/	Closed		7 (AI 7)	17 - 18
	Night			8 (AI 8)	19 -20
	Door	/
	Level	Open		9 (DO 1)	25 - 26 - 27
	switch
				10 (DO 2)	28 - 29 - 30
DO
	Comp 1			11 (DO 3)	31 - 30 - 33
	Comp 2	Active at:		12 (DO 4)	34 - 35 - 36
	Fan 1
	Alarm			13 (DO 5)	37 - 38 - 39
	Light	on
	Rail heat	/		14 (DO6)	40 - 41 - 42
	Defrost	Off		15 (DO7)	43 - 44 - 45
	Solenoid
	valve			16 (DO8)	46 - 47 - 48
22 | BC245386497365en-000801					© Danfoss | Climate Solutions | 2022.02

User Guide | Pack controller, type AK-PC 782A

2.3.6 Extension module AK-XM 208C

Function

The module contains:

8 analogue inputs for sensors, pressure transmitters, voltage signals and contact signals.

4 outputs for stepper motors.

Supply voltage

The supply voltage to the module comes from the previous module in the row. Here supplied with 5 VA.

An additional and separated power supply must be installed, which must be galvanically separated from the supply for the control range. Class II is required.

(Power requirements: 7.8 VA for controller + xx VA per valve).

2 separated UPS´s are recommended, one for the pack controller and another AK-XM 208C module if the valves need to open/ close during a power failure. If the AK-CM 102 module is installed it is also recommended a separated UPS.

Light-emitting diodes

There is one row with LEDs, indicating the following:

•Voltage supply to the module

•Communication active with the bottom PC board (red = error)

•Step1 to step4 OPEN: Green = Open

•Step1 to step4 CLOSE: Green = Close

•Red flash = Error on motor or connection

	Separate voltage supply
	is required	max. 10 V
	24 V AC/DC / fx. 13 VA

<![if ! IE]>

<![endif]>L = max. 30 m

Output:

24 V DC

20-500 step/s

Max. Phase current = 325 mA RMS

∑ Pmax. = 21 VA

The connection to the valve must not be broken using a relay.

Valve data

Type	P
ETS 12.5 - ETS 400	1.3 VA
KVS 15 - KVS 42
CCMT 2 - CCMT 8
CCM 10 - CCM 40
CTR 20
CCMT 16 - CCMT 42	5.1 VA
CCMT - 3L/5L/8L	4.0 VA

Power supply to AK-XM 208C:

Fx: 7.8 + (4 x 1.3)	= 13 VA	AK-PS 075
Fx: 7.8 + (4 x 5.1)	= 28,2 VA	AK-PS 150

© Danfoss | Climate Solutions | 2022.02

BC245386497365en-000801 | 23

User Guide | Pack controller, type AK-PC 782A

Point

CCMT

Point	1	2	3	4	5	6	7	8
Type	AI1	AI2	AI3	AI4	AI5	AI6	AI7	AI8

Terminal 17: 12 V max. 100 mA in total.

Terminal 18: 5 V max. 100 mA in total.

Terminal 19, 20: (Cable screen)

Point	9	10		11	12
Step	1	2		3	4
Type			AO

	1	25	26	27	28
Step /	2	29	30	31	32
Terminal	3	33	34	35	36
	4	37	38	39	40
ETS
CCM / CCMT		White	Black	Red	Green
CTR
KVS

Valve	Module	Step	Terminal
		1 (point 9)	25 - 28
		2 (point 10)	29 - 32
		3 (point 11)	33 - 36
		4 (point 12)	37 - 40

24 | BC245386497365en-000801

© Danfoss | Climate Solutions | 2022.02

User Guide | Pack controller, type AK-PC 782A

2.3.7 Extension module AK-OB 110

Function

The module contains two analogue voltage outputs of 0 – 10 V.

Supply voltage

The supply voltage to the module comes from the controller module.

Placing

The module is placed on the PC board in the controller module.

Point

The two outputs have points 24 and 25. They are shown on the earlier page where the controller is also mentioned.

Max. load

I < 2.5 mA

R > 4 kohm

Accuracy

Analog outputs: +/- 100 mV

		Module		1
		Point	24	25
AO		Type	AO1	AO2
				AO2
	AO	0 - 10 V		AO1

© Danfoss | Climate Solutions | 2022.02

BC245386497365en-000801 | 25

User Guide | Pack controller, type AK-PC 782A

2.3.8 Extension module EKA 163B / EKA 164B

Function

Display of important measurements from the controller, e.g. appliance temperature, suction pressure or condensing pressure. Setting of the individual functions can be performed by using the display with control buttons.

It is the controller used that determines the measurements and settings that can occur.

	Connection
	The extension module is connected to the controller module via
	a cable with plug connections. You have to use one cable per	EKA 163B	EKA 164B
	module. The cable is supplied in various lengths.

Both types of display (with or without control buttons) can be connected to either display output A, B, C and D.

Ex.

A: P0. Suction pressure in °C.

B: Pc. Condensing pressure in °C.

When the controller starts up, the display will show the output that is connected.

- - 1 = output A - - 2 = output B etc.

Placing

The extension module can be placed at a distance of up to 15 m from the controller module.

Point

No point has to be defined for a display module – you simply connect it.

2.3.9 Graphic display MMIGRS2

Function

Setting and display of values in the controller.

Connection

The display connects to the controller via a cable with RJ11 plug connections.

Supply voltage

Received from the controller via cable and RJ11 connector. Do not connect a seperate power supply for this display.

Termination

The display must be terminated. Mount a connection between the terminals H and R.

(AK-PC 782A is terminated internally.)

Placing

The display can be placed at a distance of up to 3 m from the controller.

Point / Address

No point has to be defined for a display – you simply connect it. However, the address must be verified. See the instructions accompanying the controller.

To create access, the display must be connected and the address of MMIGRS2 must be activated.

Setting:

1.Press both the "x-button" and "enter button" and hold for 5 seconds. Subsequently the Bios menu is shown.

2.Select the line "MCX selection", press "enter"

3.Select the line "Man selection", press "enter"

4.The address is shown now. Please check that it is 001, press "enter". Then data is downloaded from the controller.

26 | BC245386497365en-000801

© Danfoss | Climate Solutions | 2022.02

User Guide | Pack controller, type AK-PC 782A

2.3.10 Power supply module AK-PS 075 / 150 / 250

Function

24 V supply for controller.

Supply voltage

230 V AC or 115 V AC (from 100 V AC to 240 V AC)

Placing

On DIN-rail

Effect

Type	Output tension	Output current	Power
AK-PS 075	24 V DC	0.75 A	18 VA
AK-PS 150	24 V DC (adjustable)	1.5 A	36 VA
AK-PS 250	24 V DC (adjustable)	2.5 A	60 VA

Dimension

Type	High	Width
AK-PS 075	90 mm	36 mm
AK-PS 150	90 mm	54 mm
AK-PS 250	90 mm	72 mm

Class II

Supply to a controller

Connections

AK-PS 075
						AK-PS 150		AK-PS 250

© Danfoss | Climate Solutions | 2022.02

BC245386497365en-000801 | 27

User Guide | Pack controller, type AK-PC 782A

2.3.11 Communication module AK-CM 102

Function

The module is a new communication module, meaning the row of extension modules can be interrupted.

The module communicates with the regulator via data communication and forwards information between the controller and the connected extension modules.

Connection

Communication module and controller fitted with RJ 45 plug connectors.

Nothing else should be connected to this data communication; a maximum of 5 communication modules can be connected to one controller.

Communication cable

One metre of the following is enclosed:

ANSI/TIA 568 B/C CAT5 UTP cable w/ RJ45 connectors.

Positioning

Max. 30 m from the controller

(The total length of the communication cables is 30 m)

Supply voltage

24 volt AC or DC should be connected to the communication module.

The 24 V can be sourced from the same supply that supplies the controller. (The supply for the communication module is galvanically separated from the connected extension modules). The terminals must not be earthed.

The power consumption is determined by the power consumption of the total number of modules.

The controller strand load must not exceed 32 VA. Each AK-CM 102 strand load must not exceed 20 VA.

Point

Connection points on the I/O modules should be defined as if the modules were an extension of each other.

Address

The address for the first communication module should be set to 1. Any second module should be set to 2. A maximum of 5 modules can be addressed.

Termination

The termination switch on the final communication module should be set to ON.

The controller should permanently be set to = ON.

Warning!

Additional modules may only be installed following the installation of the final module. (Here following module no. 11; see the sketch.)

After configuration, the address must not be changed.

Max. 32 VA

Max. 20 VA

Max. 20 VA

28 | BC245386497365en-000801

© Danfoss | Climate Solutions | 2022.02

User Guide | Pack controller, type AK-PC 782A

2.4 Preface to design

Be aware of the following when the number of extension modules is being planned. A signal may have to be changed, so that an additional module may be avoided.

•An ON/OFF signal can be received in two ways. Either as a contact signal on an analogue input or as voltage on a low or high-voltage module.

•An ON/OFF output signal can be given in two ways. Either with a relay switch or with solid state. The primary difference is the permitted load and that the relay switch contains a cut-out switch.

Functions

Clock function

Clock function and change-over between summer time and winter time are contained in the controller.

The clock setting is maintained for at least 12 hours at a power failure.

The clock setting is kept updated if the controller is linked up in a network with a system manager.

Start/stop of regulation

Regulation can be started and stopped via the software. External start/stop can also be connected.

Warning!

The function stops all regulation, including any high-pressure regulation.

Excess pressure can lead to a loss of charge.

Start/stop of compressors

External start/stop can be connected.

Alarm function

If the alarm is to be sent to a signal transmitter, a relay output will have to be used.

Mentioned below are a number of functions and connections that may have to be considered when a regulation has to be planned. There are more functions in the controller than the ones mentioned here, but those mentioned have been included in order for the need for connections to be established.

I'm alive function

A relay can be reserved which is pulled during normal regulation. The relay will be released if the regulation stops with the main switch or if the controller fails.

Extra temperature sensors and pressure sensors

If additional measurements have to be carried out beyond the regulation, sensors can be connected to the analogue inputs.

Forced control

The software contains a forced control option. If an extension module with relay outputs is used, the module’s top part can be with change-over switches – switches that can override the individual relays into either OFF or ON position.

Wiring should be done with a safety relay. See Regulating functions.

Data communication

The controller module has terminals for LON data communication. The requirements to the installation are described in a separate document.

© Danfoss | Climate Solutions | 2022.02

BC245386497365en-000801 | 29

User Guide | Pack controller, type AK-PC 782A

Connections

In principle there are the following types of connections:

Analogue inputs ”AI”

This signal must be connected to two terminals.

Signals can be received from the following sources:

• Temperature signal from Pt 1000 ohm temperature sensor

• Pulse signal or reset signal

•Contact signal where the input is shortcircuited or ”opened”, respectively

• Voltage signal from 0 to 10 V

• Signal from pressure transmitter AKS 32, AKS 32R, AKS 2050 or MBS 8250.

• The supply voltage is supplied from the module’s terminal board where there is both a 5 V supply and a 12 V supply. When programming, the pressure

transmitter’s pressure range must be set.

ON/OFF voltage inputs ”DI”

This signal must be connected to two terminals.

• The signal must have two levels, either 0 V or ”voltage” on the input. There are two different extension modules for this signal type:

–low-voltage signals, e.g. 24 V

–high-voltage signals, e.g. 230 V

When programming, the function must be set:

•Active when the input is without voltage

•Active when voltage is applied to the input.

ON/OFF output signals ”DO” There are two types, as follows:

• Relay outputs

All relay outputs are with change-over relay so that the required function can be obtained when the controller is without voltage.

• Solid state outputs

Reserved for ejector valves, oil valves and AKV valves, but output can cut an external relay in and out, as with a relay output.

The output is only found on the controller module.

When programming, the function must be set:

•Active when the output is activated

•Active when the output is not activated.

Analogue output signal ”AO”

This signal is to be used if a control signal is to be transmitted to an external unit, e.g. a frequency converter.

When programming, the signal range must be defined: 0-5 V, 1-5 V, 0-10 V or 2-10 V.

Pulse signal for the stepper motors.

This signal is used by valve motors of the type ETS, KVS, CCM and CCMT.

The valve type should be set during programming.

Limitations

As the system is very flexible regarding the number of connected units, you must check whether your selection complies with the few limitations there are.

The complexity of the controller is determined by the software, the size of the processor, and the size of the memory. It provides the controller with a certain number of connections from which data can be downloaded, and others where coupling with relays can be performed.

The sum of connections cannot exceed 220 (AK-PC 782A).

The number of extension modules must be limited so that the total power in a row will not exceed 32 VA (including controller). If the AK-CM 102 communication module is used, each row of AK-CM 102 must not exceed 20 VA (incl. AK-CM 102). There must not be more than a total of 18 modules (controller + 17 modules).

No more than 5 pressure transmitters may be connected to one controller module.

No more than 5 pressure transmitters may be connected to one extension module.

Common pressure transmitter

If several controllers receive a signal from the same pressure transmitter, the supply to the affected controllers must be wired so that it is not possible to switch off one of the controllers without also switching off the others. (If one controller is switched off, the signal will be pulled down, and all the other controllers will receive a signal which is too low).

Ejector valves

If ejector valves are used, the smallest ones must be connected to the solid state outputs.

30 | BC245386497365en-000801

© Danfoss | Climate Solutions | 2022.02