Danfoss Ekc 414a User manual

REFRIGERATION AND

AIR CONDITIONING

Controller for controlling one evaporator

EKC 414A

Manual

2 Manual RS8CK502 © Danfoss 05-2005 EKC 414A

Introduction

Application

The controller is a complete control unit for refrigeration appli-

ances with integrated refrigeration-technical functions capable of

replacing a setup of thermostats and timers.

The relays are used for operating:

- Compressor

- Fan

- defrost

- Alarm

- Light

The controller can operate one evaporator.

The intended placing of the controller is “on/near the refrigeration

appliance” and the controller is therefore provided with plugs at

the sensor connection points. All sensors used must therefore be

ﬁtted with a belonging plug.

Operation

The controller comes without operating buttons on the front

panel, and it will require no operation once it has been set and

started up.

When the controller is operated, it can be done in one of the fol-

lowing ways:

• Connection of an external display with operating buttons

- The display will currently show measurements and settings in

the menu system

- In case of malfunction the relevant error code will be shown on

the display

- Four light-emitting diodes will show the system’s actual func-

tion:

› refrigeration

› power for the AKV valve

› defrost

› fan operating

› when there is an alarm the three LED’s will ﬂash

• Data communication

The controller can be hooked up with other products in the

series of ADAP-KOOL® refrigeration controls. The operation,

monitoring and data collection can then be performed from a

PC – either on site or at a service company.

Customer display

If the temperature in the appliance is to be visible to, say, custom-

ers, a display can be mounted.

Inject ON function

The expansion valve closes when the signal at the 230V input is

removed or receives a signal via the data communication. In this

way it is ensured that the expansion valve will not charge the

evaporator when the compressor has stopped.

(The threading of the function may be cancelled via a setting).

Digital input

A digital input can be deﬁned for one of the following applica-

tions:

Door alarm

Defrost start

Night operation

Start/stop of regulation

Joint defrost start/stop with a master/slave function

Data communication

The controller is provided with LON RS 485 data communication.

More about this data communication on page 18.

EKC 414A Manual RS8CK502 © Danfoss 05-2005 3

Function

Liquid supply

The supply of liquid is controlled on the basis of signals from the

pressure transmitter, temperature sensor S2 and the air tempera-

ture. The sensors create a signal so that the superheat is continu-

ously kept at a minimum whatever the operating conditions.

The AKV valve functions both as expansion valve and solenoid

valve. The valve opens and closes based on signals from the

controller.

Temperature control

The temperature is controlled on the basis of signals from one

or two temperature sensors. If there is only one sensor it may

optionally be placed in the air before or after the evaporator. If

there are two sensors, one must be placed before and one after

the evaporator. With a setting it is subsequently deﬁned how

large an inﬂuence the individual sensor is to have on the control.

The actual temperature control can take place in two ways: as an

ordinary ON/OFF regulation with a belonging diﬀerential, or as

a modulating control there the temperature variation will not be

nearly as great as in ON/OFF control. There is however a limit to

the use of them as a modulating control can only be used in cen-

tral plant. In a decentralised plant the thermostat function with

ON/OFF control should be selected.

In a central plant the thermostat function may either be selected

for ON/OFF control or modulating control.

Defrost

With a simple function defrost can be started x times per day and

night. But the controller may also receive a signal from a defrost

clock or from another unit via the data communication, so that

defrost will take place at deﬁned times of the day or night.

An on-going defrost can be stopped based on temperature, nor-

mally the one measured with the S5 sensor, or it may be stopped

based on time. A combination with stop based on temperature

and with the time factor as a precautionary measure is also a pos-

sibility.

Clock module (accessory)

If the controller is mounted without data communication and

defrost has to be carried out at speciﬁc times, a clock module can

be mounted.

The controller comes prepared with plug and terminals so that the

module just has to be pushed in.

Subsequently, up to six defrosts per day can be set. The module

has battery back-up.

On / Oﬀ control

Modulating control

4 Manual RS8CK502 © Danfoss 05-2005 EKC 414A

Function Para-

meter

Operation via

data communication

Thermostat function Thermostat control

Reference

The thermostat regulates on the basis of the set value. A change of the set value can

be limited/ locked with settings in r02 and r03.

- Cutout temp

Diﬀerential

When the temperaure is higher than the reference + the set diﬀerential, the compres-

sor relay will be cut in. It will cut out again when the temperature comes down to the

set reference.

r01 Diﬀerential

Reference limitation

The controller’s setting range for the reference may be narrowed down, so that much

too high or much too low values are not set accidentally - with resulting damages.

To avoid a too high setting of the reference, the max. allowable reference value must

be lowered.

r02 Max Cutout

To avoid a too low setting of the reference, the min. allowable reference value must

be increased.

r03 Min Cutout

Temperature unit

Set here if the controller is to show temperature values in °C

or in °F.

r05 Temp. unit

°C=0

(Only °C on AKM, whatever the set-

ting)

Correction of signal from S4 (Sout)

Compensation possibility through long sensor cable

r09 Adjust Sout

Correction of signal from S3 (Sin)

Compensation possibility through long sensor cable

r10 Adjust Sin

Start / stop of refrigeration

With this setting refrigeration can be started and stopped.

Start / stop of refrigeration can also be accomplished with the external switch func-

tion connected to the DI input.

r12 Main Switch

Night setback value

The thermostat’s set reference will be increased by this value when the controller

changes over to night operation. (Select a negative value if there is to be cold ac-

cumulation.)

r13 Night oﬀset

Thermostat function

Here it is deﬁned how the thermostat is to operate. Either as an ordinary ON/OFF ther-

mostat or as a modulating thermostat.

1: ON/OFF thermostat

2: Modulating

When operation is ”modulating” the AKV valve will limit the ﬂow of refrigerant so that

the temperature variation will be less than for the ON/OFF thermostat.

In a decentralised plant you must select the ON/OFF thermostat setting.

The thermostat’s settings for cutout value and diﬀerential must be identical no matter

which of the two functions is selected. E.g. 5 K, if S4 is the thermostat sensor, or 3 K, if

S3 is the thermostat sensor.

For modulating thermostats the diﬀerential must not be set lower than 5 K.

r14 Therm. mode

Ref. Dif.

Survey of functions

EKC 414A Manual RS8CK502 © Danfoss 05-2005 5

Selection of thermostat sensor

Here you deﬁne the sensor the thermostat is to use for its control function. S3, S4, or

a combination of them. With the setting 0%, only S3 is used (Sin). With 100%, only S4

(Sout)

r15 Sout %

Melt function

Only for control of refrigeration (-5 to +10°C). The function ensures that the evapo-

rator will not be closed by frost. Here you set how often the function is to stop the

refrigeration and hence transform the frost to water (or ice if there is too much frost).

r16 Meltinterval

Melt period

Here you set how long an on-going melt function is to last.

r17 Melt period

NightSetback

OFF gives day operation

ON gives night operation

Alarm settings Alarm Settings

The controller can give alarm in diﬀerent situations.

When there is an alarm the light-emitting diodes (LED) will ﬂash on the front panel of

EKA 162.

Delay on temperature alarm

If one of the two limit values A13 or A14 is exceeded, a timer function will be started.

The alarm will only become visible when a set time delay is passed.

The time delay is set in minutes.

A03 Alarm delay

Time delay for door alarm

If the digital input is used for a door monitoring function (see deﬁnition in the ”Mis-

cellaneous” section) an alarm will not be given until a given period with open door

has elapsed.

The time delay is set in minutes..

A04 Door Open del

Time delay for cooling

This time delay is used during start-up, during defrost, immediately after a defrost,

and when the ON function has been used. There will be change-over to the normal

time delay (A03) when the temperature has dropped below the set upper alarm limit.

The time delay is set in minutes.

A12 Pulldown del

Upper alarm limit

Here you set when the alarm for high temperature is to start. The limit value is set in

°C (absolute value). The limit value will be raised during night operation. The value is

the same as the one set for night setback, but will only be raised if the value is posi-

tive.

A13 High Lim Air

Lower alarm limit

Here you set when the alarm for low temperature is to start. The limit value is set in °C

(absolute value).

A14 Low Lim Air

Reset alarm

The function resets all alarms when set

in pos. ON.

EKC error

Here you can read the alarm status.

Compressor function Compressor control

The compressor relay works in conjunction with the thermostat. When the thermostat

calls for refrigeration will the compressor relay be operated.

Running times

To prevent irregular operation, values can be set for the time the compressor is to run

once it has been started. And for how long it at least has to be stopped.

Min. ON-time (in minutes) c01 Min. On time

Min. OFF-time (in minutes) c02 Min. Oﬀ time

6 Manual RS8CK502 © Danfoss 05-2005 EKC 414A

Defrost Defrost control

A defrost can be started in ﬁve ways: via the data communication, via a signal at the

DI input, via clock module and setting, via an internal timer function or by a pushon

the lower of the displays’ control buttons. It is recommended to set the timer func-

tion even if one of the three ﬁrst options is used. The timer function will then act as

safety period if the original defrost start should be overdue. The defrost itself can be

stopped based on time, or a temperature sensor can be placed on the evaporator so

that defrost can be stopped based on temperature value.

Defrost stop temperature

If a defrost sensor has been mounted on the evaporator, the defrost can be stopped

at a given temperature. The temperature value is set. If a defrost sensor has not been

mounted, the defrost will be stopped based on time.

Cf. d4 and d10.

d02 Def. Stop Temp

Interval between defrost starts

It is recommended to start the defrost via the data communication or via a signal at

the DI input and then use this setting as precautionary measure if the normal defrost

signal should fail to appear (the time interval must be greater than the time between

two normal defrost starts).

But the interval function may also be used as a simple defrost start function where

the defrost is started periodically, say, every eight hours. If defrost is to be performed

at speciﬁc times of the day, the setting must be made accordingly. (The internal coun-

ter is zeroset after a power failure).

The time interval is reset at each defrost start.

d03 Def.Interval

Max. defrost duration

If you have chosen to stop defrost based on temperature, this setting will constitute a

safety period where the defrost will be stopped if no stop based on temperature has

taken place by then. If you have selected defrost stop based on time, this setting will

be the defrost time.

d04 Max Def.time

Time displacement of defrost cutins during start-up

The function is only relevant, if you have several refrigeration appliances or groups

where you would like the defrost to be displaced. This function is also only relevant if

you have selected defrost with interval start (d03).

The function delays the defrost by the set number of minutes, but for the very ﬁrst

defrost it only does it when the controller has been energised.

d05 Time stagg.

Drip-oﬀ time

Here you set the time that is to elapse from the end of a defrost and until compressor

is to be resumed. (The time when water is dripping oﬀ the evaporator).

d06 Drip Oﬀ time

Fan start delay after defrost

Here you set the time that is to elapse from when the compressor is started after a

defrost and until the fan may resume operation. (The time where the water is “bound”

to the evaporator).

d07 Fan Start Del.

Fan start temperature

The fan may also be started a little earlier than mentioned under “Delayed fan start

after defrost” if the defrost sensor registers a permissible value. Here you can set the

value for when the fan may start.

d08 Fan Start Temp.

Fan cut in during defrost

Here you set whether the fan is to operate during defrost.

If the ON function is selected, the settings in d07 and d08 are not relevant

d09 Fan During Def.

Defrost sensor

Here you set whether the defrost sensor is to beS4, S5 or if there is not going to be a

defrost sensor at all.

0: S4 (Sout)

1: S5 (Sdef)

2: No defrost sensor. Defrost stop is based on time.

d10 Def Stop Sensor

Defrost at power up

Here you set whether the controller is to start with a defrost when power is supplied

to the controller during start-up or after a power failure. The function ensures that

defrost will be performed on weak networks with frequent power failures.

d13 Def. At Power Up

Def. start

Here you can start a manual defrost

Hold After Def.

Shows ON when the controller is

operating with coordinated defrost.

EKC 414A Manual RS8CK502 © Danfoss 05-2005 7

Injection control Injection control

Max. value for the superheat reference n09 Max SH

Min. value for the superheat reference n10 Min SH

MOP temperature

If no MOP function is required, select pos. OFF

n11 MOP temp.

(A value of 15 corresponds to OFF)

The settings in n13 to n18 are adapted to evaporators in central plants. In decentralised plants it may be necessary to make

adjustments. HOWEVER, they should only be carried out by trained staﬀ.

AKV valve’s time period in seconds

Should only be set to a lower value if it is a decentralised plant and the suction pres-

sure ﬂuctuates a lot and in line with the opening of the AKV valve.

The value should only be changed by specially trained staﬀ.

n13 AKV period

Adaptive control

With adaptive control the controller will itself adjust the valve’s opening degree so

that the evaporator all the time has the minimum permissible superheat (MSS). If the

function is set in pos. OFF, the settings in n16 and n17 will be used in the control. The

OFF setting should only be made by specially trained staﬀ

n14 Adap. inject

Average opening degree

The controller registers the valve’s opening degree continuously and uses the value in

its regulation (in the KP factor for the injection algorithm).

The value should only be changed by specially trained staﬀ.

n16 AKV Dim

Start-up time for signal reliability

The controller uses the value for each thermostat cutin where the evaporator is to be

charged quickly.

(In a decentralised plant the value must be lower than the factory setting – a high

value may result in a ﬂooded evaporator).

The value should only be changed by specially trained staﬀ.

n17 Start OD%

Stability factor for regulation of superheat

With a higher value the control function will allow a greater ﬂuctuation of the super-

heat before the reference is changed.

The value should only be changed by specially trained staﬀ.

n18 Stability

Forced closing

The AKV valve will close when the function is set in pos. ON.

(It will also close when the "Inject ON " input is de-energised).

n36 Inject Close

8 Manual RS8CK502 © Danfoss 05-2005 EKC 414A

Fan control Fan control

In addition to the fan functions during defrost the fans may also be stopped as a func-

tion of the compressor operation and if necessary a door function.

Fan stop on compressor cut out

Here you can select whether the fan must be stopped when the compressor is cut

out.

F01 Fan stop co

Delayed fan stop when compressor is cut out

If you have chosen to stop the fan when the compressor is cut out you can delay the fan

stop after the compressor has stopped. Here you set the time delay.

F02 Fan del. co

Fan stop temperature

The function stops the fans in an error situation, so that they will not provide power

to the appliance. If the defrost sensor registers a higher temperature than the one set

here, the fans will be stopped. There will be re-start at 2 K below the setting.

The function is not active during a defrost, start-up after a defrost, or if the AKV-ON

signal is interrupted.

With setting +50°C the function is interrupted.

F04 Fan Stop Temp.

Miscellaneous Miscellaneous

Delay of output signal after start-up

After start-up or a power failure the controller’s functions can be delayed so that over-

loading of the electricity supply network is avoided. Here you can set the time delay.

o01 Delay Of Outp.

Digital input control

The controller has a digital input “DI” which can be used for one of the following func-

tions:

1) Door alarm. Connect a door switch and the controller will register when the DI

input is open. Subsequently, the controller will allow the function ”door alarm”.

2) Defrost. A contact function with returm spring is ﬁtted. The controller will register

when the DI input is activated. The controller will then start a defrost cycle. If the

signal is to be received by several controllers it is important that ALL connections are

mounted the same way (DI to DI and GND to GND).

3) Night operation. Connect a switch. When the switch is cut in, there will be night

operation.

4) Main switch. Regulation is carried out when the input is short-circuited, and regula-

tion is stopped when the input is put in pos. OFF.

5) Coordinated defrost with cable connections. See wiring diagram. (If coordinated

defrost via data communication is used, setting 5 must not be used).

0) Setting should be 0 (OFF) when the DI input is not used

o02 Di 1 Conﬁg

Address

If the controller is built into a network with data communication, it must have an

address, and the master gateway of the data communication must then know this

address.

These settings can only be made when a data communication module has been

mounted in the controller and the installation of the data communication cable has

been completed.

This installation is mentioned in a separate document “RC.8A.C”..

The address is set between 1 and 60 o03

The address is sent to the gateway when the menu is set in pos. ON o04

Access code

If the settings in the controller are to be protected with an access code you can set a

numerical value between 0 and 100. If not, you can cancel the function with setting

OFF.

o05

EKC 414A Manual RS8CK502 © Danfoss 05-2005 9

Sensor type (S3, S4, S5) = (Sin, Sout, Sdef )

Normally a Pt 1000 sensor with great signal accuracy is used. But you may also use a

PTC sensor (R25 = 1000) in special situation.

o06 Sensor Conﬁg

Pt=0

PTC =1

Frequency

Set the net frequency.

o12 50 / 60 Hz

(50=0, 60=1)

Coordinated defrost with wire connections

Connections to the controller must be made as described on page 12.

Oﬀ: No coordinated defrost with wire connections

1: Master (only one controller in the group can be master)

2: Slave

If output (DO) is not used, the setting must be 0.

If the function is set in the slave prior to being set in the main controller, this will start

a defrost. This can be avoided by setting the main controller before the slave. It will

however depend on the setting at the DI input.

o13 DO 1 Conﬁg

Not used = 0

Master = 1

Slave = 2

Max. standby time after coordinated defrost

When a controller has completed a defrost it will wait for a signal which tells that the

refrigeration may be resumed. If this signal fails to appear for one reason or another,

the controller will itself start the refrigeration when this standby time has elapsed.

o16 Max Hold time

Select sensor signal for the display

With a % value you can set whether the display should show the S3 temperature, the

S4 temperature or a mixture of the two.

With setting 0%, only the S3 temperature is shown.

With setting 100%, only the S4 temperature is shown.

o17 Disp. Sout %

Manual control of outputs

In connection with service the individual relay outputs and the digital output can be

changed to pos. ON.

Oﬀ: No override

1: Compressor relay is ON

2: Defrost relay is ON

3: Fan relay is ON

4: Alarm relay is OFF

5: Signal to slave controllers that defrost is required

6: The AKV output is ON

7: Light relay is On

Remember to reset the function to OFF when forced control is terminated.

o18

Pressure transmitter’s working range

According to the pressure a pressure transmitter with a given working range is used.

This working range must be set in the controller (e.g. –1 to 12 bar).

Min. value 020 MinTransPress

Max. value o21 MaxTransPress

"Inject ON" settings

Here you deﬁne which functions are to be active when the "Inject ON" input does not

receive signals or when ”n36” is put in pos. ON:

1: The fan relay is activated. There is alarm monitoring.

2: The fan relay is not activated. There is alarm monitoring.

3: The fan relay is not activated. There is no alarm monitoring.

4: The fan relay is activated. There is no alarm monitoring.

For 3 and 4 applies that a defrost cannot be started (any defrost in progress will be

terminated in the normal way).

If the “Inject on” input is not wired the setting must be selected to 5, 6, 7 or 8.

The function is as mentioned under 1-4. (1=5, etc.).

o29 Inject Cl. Cfg

Refrigerant setting

Before refrigeration is started, the refrigerant must be deﬁned. You may choose be-

tween the following refrigerants

1=R12. 2=R22. 3=R134a. 4=R502. 5=R717. 6=R13. 7=R13b1. 8=R23. 9=R500.

10=R503. 11=R114. 12=R142b. 13=Userdeﬁned. 14=R32. 15=R227. 16=R401A.

17=R507. 18=R402A. 19=R404A. 20=R407C. 21=R407A. 22=R407B. 23=R410A.

24=R170. 25=R290. 26=R600. 27=R600a. 28=R744. 29=R1270. 30=R417A

Warning: Wrong selection of refrigerant may cause damage to the compressor.

o30 Refrigerant

10 Manual RS8CK502 © Danfoss 05-2005 EKC 414A

Service Service

A number of controller values can be printed for use in a service situation

Read the temperature at the S5 (Sdef) sensor (calibrated value) u09 Sdef temp.°C

Read status of input DI u10 DI 1 status

Read the duration of the ongoing defrost or the duration of the last completed

defrost.

u11 Defrost time (Depicted in the ”Defrost

control” illustration)

Read the temperature at the S3 (Sin) sensor (calibrated value) u12 Sin air temp

Read status at the day-/night operation (night operation: on/oﬀ) u13 Night Cond (Depicted in the ”Thermo-

stat control” illustration)

Read status at the ON input u14 Inject ON

Read status at the DO output u15 DO 1 status

Read the temperature at the S4 (Sout) sensor (calibrated value) u16 Sout Air Temp.

Read the temperature according to which the thermostat function regulate u17 Ther. air

Read the ongoing cutin time for the thermostat or the duration of the last completed

cutin

u18 Ther. runtime (Depicted in the ”Ther-

mostat control” illustration)

Read the temperature at the S2 sensor u20 S2 temp.

Read superheat u21 SH (Depicted in the ”Injection control”

illustration)

Read the control’s actual superheat reference u22 SH ref. (Depicted in the ”Injection

control” illustration)

Read the valve’s actual opening degree u23 AKV OD%

Read the evaporating pressure in bar u25 Evap. pres. P0

Read the evaporating pressure in degrees u26 Evap. temp. T0

Compressor relay