Danfoss EET Series User manual

User Guide
Refrigeration controller
Type EETc and EETa series
Enhanced Electronic Thermostat

Contents
Introduction 4
Variants 4
Applications 4
Key features 4
Functions 5
Voltage protection 5
Compressor protection against short cycling 5
Zero Cross Technology 5
Compressor protection against high condensing temperature 6
Advanced Fan control 6
Initial pull down 7
Automatic Pull down (applicable for EETa only) 7
Economy mode 8
Holiday mode (applicable for EETa only) 8
Dual evaporator defrost (applicable for EETa only) 8
Dual compressor control (applicable for EETa only) 8
Anti Freeze function (applicable for EETa only) 9
Quick Test mode 9
Sensor Error handling 9
Potentiometer Error handling 9
Installation 10
Dimensions 10
Connections 11
Mounting 12
Wire routing 13
Accessories 13
KoolKey 13
Mass Programming Key (EKA 201) 13
Bluetooth Adapter (EKA 202 & EKA 203) 14
Product specication 15
Technical specication 15
Parameters 17
EETc 11, 12, 21 and 22 17
Refrigeration controller, type EET series
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Assignment 17
Thermostat 17
Compressor 17
Alarm 18
Defrost 18
Fan 19
ECO Management 19
System protection 20
Test Mode 20
Service 20
EETa 2W and EETa 3W 21
Assignment 21
Thermostat 22
Compressor 22
Alarm 22
Defrost 23
Fan 24
Light 24
ECO Strategy 24
Automatic Heater Control 25
System protection 25
Test Mode 26
Service 26
Troubleshooting and Alarms 28
Troubleshooting 28
Alarms 28
Ordering 29
Certicates, declarations, and approvals 30
Online support 31
Refrigeration controller, type EET series
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Introduction
The EET Series is the next generation of Electronic Thermostats which is a direct replacement of the Mechanical
Thermostat (and timer) and Danfoss ETC series. It comes in two variants: EETc (Enhanced Electronic Thermostat,
compact) which has one and two output model options for controlling compressor and fan/defrost heater and EETa
(Enhanced Electronic Thermostat, advanced) which has two and three output model options for controlling
compressor, fan, defrost heater or light. With the EETc and the EETa, we continue building on the electronication
legacy by bringing a high number of new features and capabilities to increase performance and exibility, while
keeping the familiar form factor and installation method.
Variants
EET Compact (EETc):
• EETc 11: 1 output, 120 V
• EETc 12: 1 output, 230 V
• EETc 21: 2 outputs, 120 V
• EETc 22: 2 outputs, 230 V
EET Advanced (EETa):
• EETa 2W: 2 outputs, wide voltage (100 – 240 V)
• EETa 3W: 3 outputs, wide voltage (100 – 240 V)
Applications
• Glass door merchandisers
• Beverage coolers
• Commercial freezers and refrigerators
• Preparation tables, under counters
• Dual compressor refrigerators (EETa only)
• Anti-freeze applications requiring auto heat control (EETa only)
• Applications requiring dual defrost control (EETa only)
Key features
Table 1: Key features
Key features
EETc
EETa
Common interface for easy transition from ETC series and Mechanical Thermostat
Yes
Yes
Moisture protected design for cold space installation
Yes
Yes
Zero cross technology for longer relay life
Yes
Yes
Compressor protection from voltage uctuations.
Yes
Yes
Compressor protection from condenser overheat
Yes
Yes
Advanced fan control
Yes
Yes
Economy mode (Eco mode) for energy saving
Yes
Yes
Initial pull down for faster cooling at power up.
Yes
Yes
Test mode for quick checking of output function
Yes
Yes
Emergency mode in case of sensor and potentiometer failure
Yes
Yes
Parameter programmable at production site with direct programming key access
Yes
Yes
Refrigerant leakage detection
No
Yes
Wide Voltage Power supply
No
Yes
Holiday mode for energy saving
No
Yes
Dual evaporator defrost
No
Yes
Dual compressor control
No
Yes
Automatic Pull down for faster cooling
No
Yes
Anti-freeze function for low ambient conditions
No
Yes
Onsite rmware update capability
No
Yes
Refrigeration controller, type EET series
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uHi
uLi
uLo
Danfoss
80G408
V
uHi
V
uLo
uLi
Maximum voltage limit above which the
compressor is switched o
Supply voltage
Minimum voltage limit below which the
compressor is switched o
Minimum voltage limit above which the
compressor can start
Functions
Voltage protection
The voltage protection feature protects the compressor against high and low voltage uctuations by limiting the
compressor operation within specied voltage limits. Whenever the supply voltage goes beyond the dened
voltage limits set in the controller, it will switch the compressor OFF, and resume the operation when the voltage
falls under the operating range.
Figure 1: Voltage protection
Compressor protection against short cycling
This feature protects the compressor from short ON-OFF cycles. The EET controller ensures that the compressor is
switched ON and OFF for a minimum time specied under Minimum run time (Crt) and Minimum stop time (cSt)
except during voltage and condenser protection.
Figure 2: Compressor protection against short cycling
Danfoss
80G409
min. run time
ON
OFF
CUT-IN
CUT-OFF
min. stop time
time
Temperature Power to compressor
time
Zero Cross Technology
The Zero Cross Technology controls the relay’s switching time by ensuring that the relays switch ON or OFF close to
the 0th position of the voltage curve. This ensures reduced relay contact welding, increased relay life and reduced
switching noise. This feature should only be used when the compressor is directly driven by the EET relay and no
external contactor is used.
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Refrigeration controller, type EET series

1
0.8
0.6
0.4
0.2
0
-0.2
-0.4
-0.6
-0.8
-1
0 90 180 270 360 90 180
Danfoss
80G422
BA
A
B
Break on negative edge
Break on positive edge
Figure 3: Zero Cross Technology
Compressor protection against high condensing temperature
If the condenser is blocked due to dirt / dust and the condenser is unable to cool down the refrigerant properly due
to lack of proper heat exchange, it will aect its performance and greatly reduces system life. This feature will
protect the system and compressor via a two-step protection mechanism. The controller can be congured to set an
early warning temperature by the user, when the compressor can keep running, and then a second level of
condenser temperature beyond which the compressor is switched o until the temperature comes down to an
acceptable limit. This would help to improve the compressor life by running within the allowed operating envelope
of the compressor.
Figure 4: Compressor protection against high condensing temperature
Danfoss
80G410
Condenser Temperature
Compressor
Cond alarm
Cond alarm (cAL)
Block Limit (cBL)
OK Limit (coL)
Advanced Fan control
Advanced Fan control helps maintain a uniform cooling by switching fan ON and OFF during the compressor OFF
cycle. This feature reduces the overall energy consumption while maintaining a uniform temperature in the cabinet.
Refrigeration controller, type EET series
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Figure 5: Advanced Fan control
Danfoss
80G411
Compressor cut in
Compressor cut out
Fan
Compressor
Fan ON cycle
Fan stop cycle
Fan start delay Fan stop delay
Cabinet Air
Initial pull down
If the cabinet temperature is very high at power up, the controller detects the need for faster cooling and enters into
Initial pull down mode. In this mode, the controller adjusts the defrost interval by skipping it to a later time than its
scheduled intervals until the desired cabinet temperature is achieved.
Figure 6: Initial pull down
∆ t
Cut-in
Cut-out
0 ºC
Danfoss
80G412
Without initial pull down, where defrost is initiated
With initial pull down
Initial pull down initiation (Pit)
Defrost terminate temp
Time saving, with ‘Initial pull down’
feature enabled
This ensures faster cooling by achieving the required cabinet temperature in the shortest period possible.
Automatic Pull down (applicable for EETa only)
This feature helps to achieve faster and extra cooling when there is an increase in the cabinet temperature due to
frequent door opening or fresh food products being placed in the cabinet. The faster and extra cooling is achieved
by adjusting the temperature set point and defrost intervals until the desired setpoint range is achieved. The
controller detects this mode by monitoring the cabinet temperature behaviour, also it is possible to trigger this
mode manually via a digital input switch.
Figure 7: Pull down/Super cool mode
Danfoss
80G423
> 1 hr Pdd
(pull down duration)
Pull Down Initiation (Pit)
Pull down offset temp (Pit)
Cut-in
Cut-out
Set point
(pull down initiated, when the cabinet
temp is above pit for for more than 1 hr)
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Refrigeration controller, type EET series

Economy mode
This feature helps save energy by increasing the setpoint when the normal cooling demand is not required. ECO
mode is triggered when the door is closed for more than the time specied by the parameter ‘Edd’. ECO mode can
also be triggered manually via Di input. In some cases, this feature is meant to decrease the setpoint and thereby
enabling extra cooling when the power is cheaper at night time.
Figure 8: Eco mode
Danfoss
80G413
Door Open
Door Close
Temperature
Normal mode
Eco delay
(Edd)
Eto
ECO mode Normal mode
Time
Holiday mode (applicable for EETa only)
This feature allows for more energy savings during vacation/ Holiday period by o-setting the setpoint when there
is no usage for a prolonged period. If there is no door activity detected after entering ECO mode for the period that
has been congured under parameter “Holiday length”, it enters into Holiday mode. The entry into Holiday mode
happens by time passing by and is exited by door action. Holiday mode can also be triggered manually via digital
input.
Figure 9: Holiday mode
Danfoss
80G414
Door Open
Door Close
Temperature
Normal mode
Eco delay
(Edd)
Holiday Length
(HoL)
Eto
Hto
Normal modeECO mode Holiday mode
Time
Dual evaporator defrost (applicable for EETa only)
The EETa can control refrigeration cabinets with two defrost heaters and two evaporator sensors in combination.
This feature provides more exibility to the refrigeration system design and provides the most ecient defrost
handling. The controller can control defrost with both a single heater and two evaporator sensor inputs as well as
two heaters with two evaporator sensor inputs.
Dual compressor control (applicable for EETa only)
Certain refrigeration systems need more than one refrigeration circuit to handle the cooling requirements of the
cabinet while meeting other statutory requirements (for ex: Flammable Refrigerant qty). The EETa controller comes
with a feature that can handle two compressors which can be operated with time delay (Scd).
NOTE:
The second compressor can be congured to any of the auxiliary relays and might require an external relay, if the
rated current of the second compressor is more than the auxiliary relay ratings.
Refrigeration controller, type EET series
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1.
2.
Figure 10: Dual compressor support
ON
ON
ON Cycle OFF Cycle
OFF
OFF
Compressor 1
Compressor 2
Scd
Danfoss
80G444
Anti Freeze function (applicable for EETa only)
This feature protects the bottle coolers from freezing, if they are installed outdoor with low ambient temperature.
The controller automatically switches between cooling and heating mode if the cabinet air temperature goes below
the allowed limit, thus preventing the freezing of stored products. This feature can be activated only when the
defrost type used is electrical.
Figure 11: Automatic heater control for Anti Freezing applications
Danfoss
80G421
Energy mode delay Energy mode delay
Increase in ambient
temperature
Drop in ambient
temperature
Cooling
mode
Heating
mode
Quick Test mode
This feature helps test all the outputs of the controller instantly when connected to an actual application in the OEM
Production line or during eld service. The feature can be used when connected to KoolProg or by using MODBUS
commands (please contact the Danfoss support team for info about MODBUS commands).
Sensor Error handling
In the event of cabinet sensor error/ failure, cabinet temperature can be controlled in EET controller using two
methods to avoid food spoilage until the failed sensor is replaced.
Manual Error handling: Run the compressor for xed ON and OFF time by dening error run time and error stop
time.
Auto Error handling: Smart self-learning feature of EET controller, controls the compressor cycle based on past
compressor cycles.
Potentiometer Error handling
Potentiometer error handling automatically sets the cabinet temperature to smart default setting to avoid food
spoilage in the event of a potentiometer failure.
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Refrigeration controller, type EET series

Installation
Dimensions
Figure 12: EETc
7.8
5.95
2
3.95±0.05
1.5
M10 x 0.75
Danfoss 80G400
79 mm
37.5 mm
48 mm
30.517.5
16
Figure 13: EETa
7.8
5.95
2
1.5
3.95±0.05
M10 x 0.75
83.5 mm
43.5 mm 48 mm
30.517.5
16
Danfoss 80G401
M10 x 0.75 is supplied loose.
Figure 14: Mounting plate dimensionfor EETc and EETa
11
2
Danfoss 80G402
16 mm
Recommended Mounting Plate Hole Center
Refrigeration controller, type EET series
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