Danfoss AK-RC 251 Installation guide

Installation Guide

Temperature controller for walk-in coolers

080R9291

and freezers, Type AK-RC 251

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ENGLISH

EN : Temperature controller for walk-in coolers and freezers

ES : Controlador de temperatura para cuartos fríos y congeladores

Type AK-RC 251

Warnings

•Using the unit without observing the manufacturer's instructions may alter the appliance's safety requirements. Only NTC probes supplied by Danfoss should be used for the unit to operate correctly.

•From -40 – +68 °F, if the NTC probe is extended to 3,280 ft with at least 20AWG cable, the maximum deviation will be 0.45 °F.

•It should be installed in a place protected from vibrations, water and corrosive gases, where the ambient temperature does not exceed the value indicated in the technical data.

•For the reading to be correct, the probe should be used in a place without heat influences apart from the temperature you want to measure or control.

•IP65 protection degree is only valid with the protection cover closed.

•IP65 protection degree is only valid if the cables enter the device using electrical conduit + gland with IP65 or above. The size of the glands should be suitable for the diameter of the conduit used.

•Do not spray the unit directly with high-pressure hoses, as this could cause damage.

IMPORTANT:

•Before starting the installation, you must take the advice of local regulations in force.

•The AUXILIARY relays are programmable, and their operation depends on the configuration.

•The function of the digital inputs depends on the configuration.

•The recommended currents and powers are the maximum working currents and powers.

Wiring

Always disconnect the power supply to do the wiring.

The probes and their cables should NEVER be installed in a conduit together with power, control or power supply cables.

For disconnection, the power supply circuit must be equipped with a switch of at least 2 A, 230 V, located near the device. The power supply cable will be H05VV-F or NYM 1x16/3. The section to be used as wire rated according to local regulations but must never be less than 14AWG.

Cables for relay or contactor outputs should use 14AWG, allow working temperatures equal to or over 158 °F and be installed with as few bends as possible.

The 120/230 V~ wiring must be kept clear of any other external element.

The wiring to be done depends on the type of installation. Use the appropriate diagram based on the option selected in the wizard. Check the available options on the diagrams included in the controller's packaging.

Wizard refers to a built in tool to guide the user through the set up process.

Maintenance

•Clean the surface of the unit with a soft cloth, water and soap.

•Do not use abrasive detergents, gasoline, alcohol or solvents, as this might damage the unit.

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Keypad

Pressing it for 3 seconds activates/deactivates Stand-By mode. In this mode, regulation is paused and the icon is displayed. In the programming menu, this exits the parameter without saving changes, returns to previous level or exits programming.

Pressing once displays the temperature of probe S2 for 10 seconds (If it is enabled). Pressing it for 3 seconds starts/stops the defrost.

In the programming menu, this allows scrolling around the different levels, or, during the setting of a parameter, changing its value.

Pressing it for 3 seconds activates/deactivates continuous cycle mode.

In the programming menu, this allows scrolling around the different levels, or, during the setting of a parameter, changing its value.

Pressing once activates/deactivates the cold room light.

Pressing it for 3 seconds accesses the condensed programming menu. Pressing it for 6 seconds accesses the expanded programming menu.

In the programming menu, this accesses the level shown on the display or, during the setting of a parameter, accepts the new value.

Pressing once displays the current effective value of the Set Point, taking into consideration temporary modifications by other parameters (C10 or C12).

When an alarm is underway, pressing once mutes the acoustic alarm. Pressing for 3 seconds accesses the Set Point setting.

Indicators

Fixed: Stand-By Mode activated. Regulation is paused.

Flashing: Controlled shutdown process for the regulation underway.

Fixed: Cold room door open.

Flashing: The door has been open for a greater time than has been defined in parameter A12.

There is an active alarm, but not an active HACCP alarm.

Fixed: HACCP alarm active.

Flashing: HACCP alarm registered and unconfirmed. Press the key to confirm an HACCP alarm.

Fixed: Evaporator fans active.

Flashing: The evaporator fans should be active but a delay is preventing this. (Refer to the Drip time section of the Manual for details).

Fixed: The cold solenoid is active.

Flashing: The solenoid should be active but a delay or protection is preventing this. (Refer to the Fan start-up section of the Manual for details).

Fixed: Compressor active.

Flashing: The compressor should be active but a delay or protection is preventing this. (Refer to the Compressor Protection timing section of the Manual for details).

Defrost relay active.

Continuous cycle mode active.

Cold room light active.

Alarm underway muted.

Temperature displayed in ° Fahrenheit / ° Centigrade.

Programming mode active.

STAND-BY

If the temperature regulation cannot be instantly stopped due to its configuration, a controlled stop process starts and the icon flashes. To stop the controlled stop process and force the step to Stand-by, press the Stand-by key again for 3 seconds.

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Initial configuration

The first time the unit is powered up, it will enter into the Wizard mode. The display will show the message flashing with 0.

Step 1:

Select the most suitable InI option based on the type of installation to be carried out and press SET. The available options will be shown in the following table:

InI	Type of installation							Parameters							Diagram to
	Cold regulation	Defrost	Evaporator fans	o00	I00	I10	I11		I20		I21	d1	d7	F3	be used
0	Demo Mode: it displays the temp. but does not regulate or activate relays
1	Solenoid	Electric	Yes	0	2	0	0		0		0	20	0	0	A
3	Solenoid + compressor	Electric	Yes	1	2	0	0		0		0	20	0	0	B
4	Solenoid	Air	Yes	0	1	0	0		0		0	20	1	1	A
6	Solenoid + compressor	Air	Yes	1	1	0	0		0		0	20	1	1	B
11	Solenoid	Static	No	0	1	0	0		0		0	20	1	-	A
13	Solenoid + compressor	Static	No	1	1	0	0		0		0	20	1	-	B

Note: Additional quick set up choices, including hot gas and reversed cycle options are detailed in the User Manual.

Step 2:

Use keysandto enter the desired Temperature Set Point value and press SET. The wizard has finished. The unit will begin to regulate the temperature.

If this is not the first time you use the wizard, after completing the last step the display will show the message dFp (default parameters). You may choose between two options:

0: Only parameters included in the wizard will be modified

1: Parameters modified by the wizard will be changed, all other parameters will return to their factory setting.

Important: The wizard will start automatically only on the first power on. To enter the wizard mode, initiate Stand-By mode by pressing the key for 3 seconds and wait until the unit completely halts the temperature regulation

(The indicator will light up permanently) and press the following keys in sequence,,, SET.

Wizard parameters list

	o00	Configuration of relay AUX1	0=Deactivated	1=Compressor/Crankcase heater
			2=Light	3=Virtual control
	I00	Connected probes	1=Probe 1 (Cold room)	2=Probe 1 (Cold room) + Probe 2 (Evaporator)
			0= Deactivated	1=Door contact	2=External alarm
	I10	Configuration of digital input 1	3=Severe external alarm	4=Change of SP	5=Remote defrost
			6=Defrost block	7= Low pressure switch	8=Remote Stand-by
	I11	Polarity of the digital input 1	0=Activates on closing contact	1=Activates on opening contact
			0= Deactivated	1=Door contact	2=External alarm
	I20	Configuration of digital input 2	3=Severe external alarm	4=Change of SP	5=Remote defrost
			6=Defrost block	7=Register probe	8=Probe 2° evaporator
			9=High pressure switch for Hot Gas	10=Remote Stand-by
	I21	Polarity of the digital input 2	0=Activates on closing contact	1=Activates on opening contact
	d1	Maximum defrost duration (0=defrost deactivated)
	d7	Type of defrost	0=Resistors	1=Air/fans	2=Hot gas
			3=Reversal of cycle
	F3	Status of the fans during the defrost	0=Shut down	1=Running

For more details, full User Manual and other information, scan the QR code.

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Configuration

Condensed programming menu

Enables the rapid configuration of the most frequently-used parameters (SP, C1, d0, d1, d4, F3, A1 and A2). Press the SET key for 3 seconds to access it.

Extended programming menu

Use the extended programming menu to configure all of the unit’s parameters in order to adapt it to installation requirements. Press the SET key for 6 seconds to access it.

Important:

•If the function of the password has been configured as a keypad block (b10=2), or as an access block to parameters (b10=1), you will be requested to enter the access code programmed in PAS when attempting to access either of the two functions. If the entered password is not correct, the unit will go back to showing the temperature.

•Certain parameters or menus may not be visible depending on the configuration of the rest of the parameters.

Regulation and control

	Level 1	Level 2	Description	Values	Min.	Def.	Max.
		SP	Temperature setting (Set Point)	ºF	-58	32.0	210
		C0	Probe 1 calibration (Offset)	ºF	-36.0	0.0	36.0
		C1	Probe 1 differential (Hysteresis)	ºF	0.1	3.6	36
		C2	Set Point top locking (it cannot be set above this value)	ºF	-58	210	210
		C3	Set Point bottom locking (it cannot be set below this value)	ºF	-58	-58	C2
			Type of delay for the protection of the compressor:
		C4	0=Minimum time of compressor in OFF		0	0	1
			1=Minimum time of compressor in OFF and in ON in each cycle
		C5	Protection delay time (Value of the option selected in parameter C4)	Min.	0	0	120
			COOL relay status with fault in probe 1:
		C6	0=OFF; 1=ON; 2=Average according to last 24 h prior to probe error		0	2	3
			3=ON-OFF according to prog. C7 and C8
		C7	Relay time in ON in the event of probe 1 failure	Min.	0	10	120
			(If C7=0 and C8≠0, the relay will always be disconnected in OFF)
		C8	Relay time in OFF in the event of probe 1 failure	Min.	0	5	120
	rE		(If C8=0 and C7≠0, the relay will always be connected in ON)
		C9	Maximum duration of the continuous cycle mode. (0=deactivated)	H.	0	0	48
			Variation of the Set Point (SP) in continuous cycle mode. When it reaches this point
		C10	(SP+C10), it reverts to the normal mode. (SP+C10 ≥ C3).	ºF	0	-90	C3-SP
			The value of this parameter is always negative, unless it is 0. (0=OFF)
		C12	Variation of the Set Point (SP) when the change Set Point function is active. (SP+C12 ≤	ºF	C3-SP	0.0	C2-SP
			C2) (0= deactivated)
		C19	Maximum start time from Pump Down	Sec.	0	0	120
			(Values between 1 and 9 seconds will not be accepted) (0=deactivated)
		C20	Maximum time for pump down (0= deactivated)	Min.	0	0	15
		C21	Probe to be displayed 0=All probes (sequential)		0	1	3
			1=Probe 1 (Cold Room), 2=Probe 2 (Evaporator), 3=Probe 3 (According to I20)
		C22	Stop fans and compressor on opening door 0=No, 1=Yes		0	0	1
		C23	Start-up delay for fans and compressor with door open	Min.	0	0	999
		C27	Probe 3 calibration (Offset)	ºF	-36.0	0.0	36.0
		EP	Exit to level 1

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Defrost

Level 1	Level 2	Description	Values	Min.	Def.	Max.
	d0	Defrost frequency (Time between 2 starts)	H.	0	6	96
	d1	Maximum defrost duration (0=defrost deactivated)	Min.	0	*	255
		Type of message during the defrost:
	d2	0=Displays the real temperature; 1=Displays the temperature at the start of		0	2	2
		the defrost; 2=Displays the dEF message
	d3	Maximum duration of the message	Min.	0	5	255
		(Time added at the end of the defrost process)
	d4	Final defrost temperature (by probe) (If I00 ≠ 1)	ºF	-58	46.4	122
dEF	d5	Defrost on connecting the unit:		0	0	1
		0=NO First defrost according to d0; 1=YES, First defrost according to d6
	d6	Delay of the defrost start on connecting the unit	Min.	0	0	255
	d7**	Type of defrost:		0	*	3
		0=Resistors; 1=Air/fans, 2=Hot gas; 3=Reversal of cycle
	d8	Count of time between defrost periods:		0	0	1
		0=Total real time, 1 =Sum of compressor connected time
	d9	Drip time when completing defrost (Shutdown of compressor and fans)	Min.	0	1	255
	EP	Exit to level 1

*According to wizard.

**It can only be modified using the configuration wizard (InI).

Evaporator fans

Level 1	Level 2	Description	Values	Min.	Def.	Max.
	F0	Shutdown temperature of fans	ºF	-58	113	122
	F1	Probe 2 differential if fans are shut down	ºF	0.1	3.6	36
	F2	Shut down fans when the compressor shuts down 0=No, 1=Yes		0	0	1
FAn
	F3	Status of the fans during the defrost 0=Shut down; 1=Running		0	0	1
	F4	Delay of start-up after defrost (If F3=0)	Min.	0	2	99
		It will only actuate if it is higher than d9
	EP	Exit to level 1

Alarms

	Level 1	Level 2	Description	Values	Min.	Def.	Max.
		A0	Configuration of the temperature alarms 0=Relative to SP 1=Absolute		0	1	1
		A1	Alarm for maximum in probe 1 (It should be higher than the SP)	ºF	A2	210	210
		A2	Alarm for minimum in probe 1 (It should be lower than the SP)	ºF	-58	-58	A1
		A3	Delay of temperature alarms in the start-up	Min.	0	0	120
		A4	Delay of temperature alarms from the end of a defrost	Min.	0	0	99
		A5	Delay of temperature alarms from when the A1 or A2 value is reached		0	30	99
		A6	Delay of the external alarm/Severe external alarm on receiving a signal in	Min.	0	0	120
			digital input (I10 or I20 =2 or 3)
	AL
		A7	Delay of external alarm deactivation/Severe external alarm deactivation	Min.	0	0	120
			when the signal in digital input disappears (I10 or I20=2 or 3)
		A8	Show warning if the defrost ends for maximum time, 0=No, 1=Yes		0	0	1
			Relay alarm polarity
		A9	0= Relay ON in alarm (OFF without alarm); 1= Relay OFF in alarm (ON		0	0	1
			without alarm)
		A10	Differential of temperature alarms (A1 and A2)	ºF	0.1	1.8	36
		A12	Delay of open door alarm (If I10 or I20=1)	Min.	0	10	120
		EP	Exit to level 1

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