Danfoss ERC 21 Series User manual

User Guide
Electronic refrigeration control
Type ERC 21X series
Smart multipurpose refrigeration controller

Contents
Introduction 5
Application 5
General description 5
ERC 21X series 5
ERC 211 5
ERC 213 6
ERC 214 6
Functions 8
Voltage protection 8
Compressor protection 8
Compressor protection against high condensing temperature 8
Reference displacement 9
Night mode 9
Fan cycling during compressor OFF cycle 10
Defrost on Demand 10
Applications 11
Pre-dened applications 11
ERC 211 controller 11
ERC 213 controller 11
ERC 214 controller 12
Electrical connection diagram 12
Electric noise 13
Conguration 14
Menu navigation and overview 14
Quick conguration at power up 14
Quick conguration via cFg menu 15
Parameters 18
Menu functions 18
Conguration 18
Thermostat 18
Alarm settings 19
Defrost 19
Fan 20
Electronic refrigeration control, type ERC 21X
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Compressor 20
Miscellaneous 21
Service 22
Parameters: ERC 211 22
Conguration 22
Reference 23
Alarm 23
Defrost 23
Compressor 24
Others 24
Polarity 24
Parameters: ERC 213 24
Conguration 24
Reference 25
Alarm 25
Defrost 25
Fan control 26
Compressor 26
Others 26
Polarity 27
Parameters: ERC 214 27
Conguration 27
Reference 27
Alarm 28
Defrost 28
Fan control 28
Compressor 29
Others 29
Polarity 29
Alarm code 30
Product specication 31
Technical specication 31
Mounting 31
Installation steps 32
Dimensions 32
Troubleshooting 33
Electronic refrigeration control, type ERC 21X
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Ordering 34
Sensors 34
Certicates, declarations, and approvals 35
Certicates, declarations, and approvals 35
Online support 36
Electronic refrigeration control, type ERC 21X
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Introduction
Application
ERC 21X is a smart multipurpose refrigeration controller designed to fulll today’s requirement of commercial
refrigeration applications. This controller is suitable for high, medium and low temperature applications with
natural, electrical and hot gas defrost compatibilities.
Typical applications include Glass door merchandisers, commercial fridges and freezers, cold rooms and various
other commercial refrigeration applications.
General description
ERC 21X controller comes with four push buttons, a big display, easy and intuitive menu structure and pre-dened
applications ensure ease of use. Controller is loaded with energy eciency features like smart evaporator fan
management, night mode and defrosts on demand features.
High capacity 16 A relay enable direct connection of heavy loads without use of intermediate relay: up to 2 hp
compressors depending on its power factor and motor eciency (power factor greater than 0.65 for 230 V and
greater than 0.85 for 115 V).
Safe operation of the unit is ensured through voltage protection, zero cross switching and high condenser
temperature protection features.
ERC 21X series
Three version of ERC 21X is available in both 230 V AC, 50/60HZ and 115 V AC, 60Hz.
• ERC 211: single relay output for refrigeration and heating applications.
• ERC 213: three relays outputs for ventilated refrigeration and heating applications.
• ERC 214: four relays outputs for ventilated refrigeration and heating applications.
ERC 211
ERC 211 has one relay output and two inputs (1 analogue, 1 analogue/digital). This controller can be used for either
cooling or heating applications.
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Electronic refrigeration control, type ERC 21X

Figure 1: ERC 211
Sair
Sc
DO1
Danfoss 80G8377
DI1
Outputs:
• Relay 1: compressor/solenoid valve control or simple heater in case of heating application.
Inputs:
• Input 1: control sensor (Sair).
• Input 2: condenser sensor or digital inputs that can be congured for various functions as mentioned under menu
code o02.
ERC 213
ERC 213 has three relays outputs and four inputs (2 analogues, 1 analogue/digital, 1 digital) for cooling and heating
applications.
Figure 2: ERC 213
Sair
Sc
DI1
DI2
DO2
DO3
DO1
S5
Danfoss 80G8378
Outputs:
• Relay 1: compressor/solenoid valve control or heater in case of heating applications
• Relay 2: can be congured defrost control or external alarm or cabinet light
• Relay 3: fan control
Inputs:
• Input 1: control sensor (Sair)
• Input 2: defrost sensor (S5)
• Input 3: condenser sensor (Sc) or digital input that can be congured for various functions as mentioned under
menu code o02
• Input 4: digital input that can be congured for various functions as mentioned under menu code o37
ERC 214
ERC 214 has four relays outputs and four inputs (2 analogue, 1 analogue/digital, 1 digital) for cooling applications.
Electronic refrigeration control, type ERC 21X
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Figure 3: ERC 214
Sair
Sc
DI1
DI2
DO4
DO2
DO3
DO1
S5
Danfoss 80G8379
Outputs:
• Relay 1: compressor/solenoid valve control
• Relay 2: defrost control, external alarm or cabinet light
• Relay 3: fan control
• Relay 4: this can be congured for either cabinet light or external alarm
Inputs:
• Input 1: control sensor (Sair)
• Input 2: defrost sensor (S5)
• Input 3: condenser sensor (Sc) or digital input that can be congured for various functions as metioned under
menu code o02
• Input4: digital input that can be congured for various functions as mentioned under menu code o37
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Electronic refrigeration control, type ERC 21X

Functions
Voltage protection
The voltage protection ensures that the compressor motor is operating within safe voltage ranges. If the power
supply voltage gets outside the specied high/low voltage cut-out ranges, the compressor is cut-out or restricted
from starting. Normal compressor operation is resumed when the power supply voltage is back in the area between
the high voltage cut-out limit and the low voltage cut-in limit.
Figure 4: Voltage protection
High voltage limit
Low voltage cut-in
limit (compressor start)
Low voltage cut-out
limit (alarm and
compressor stop)
Danfoss 80G8366
Compressor protection
Compressor protection feature protects compressor from short ON and OFF cycles by securing minimum run and
stop time. This would allow the refrigeration system to stabilize before starting the compressor again and also avoid
the chances of too many compressor cycles.
Figure 5: Compressor protection
Power to compressor
min run time
ON
OFF
CUT-IN
CUT-OFF
min stop time
time
time
Temperature
Danfoss 80G8375
Compressor protection against high condensing temperature
If the condenser is blocking up with dirt and thereby reaches a too high condensing temperature, the controller will
give the user early warning through condenser alarm and if temperature rises further, it will switch the compressor
OFF. If the temperature measured by the condenser sensor (Sc) is reaching the set “pre-alarm limit” an alarm is
raised, but no further action is taken. This is used to indicate to the user that something is wrong with the
condenser. Often the reason is that that the air ow to the condenser is restricted (dirt) or because the condenser
fan is broken.
The alarm will reset if the condenser temperature drops back by 5 °C. If the measured condenser temperature
continues to increase and reaches the set “Block limit” the compressor is stopped, and it is restricted from starting
again until the alarm is reset manually. The alarm can be reset manually by setting the parameter r12 Main switch to
OFF position and back to ON position or by powering the controller down.
Electronic refrigeration control, type ERC 21X
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Figure 6: Compressor protection against high condensing
temperature
Sc temperature °C
Sc temperature °C
Manual reset
Block limit
Pre alarm limit
Pre alarm OK
Compressor
Pre alarm
Block alarm
T1 T2 T3 T4
Danfoss 80G8376
Reference displacement
This feature enable user to toggle between two dierent set-points quickly by activating a switch on digital input.
This provides facility to switch between two storage temperatures without getting in to the menu. For example
meat requires dierent set points than vegetables. The reference displacement signal changes the normal
thermostat set-point and the alarm limits by a predened oset value.
Figure 7: Reference displacement
Danfoss 80G8474
Cabinet temp.
Thermostat ref. disp.
Thermostat ref. disp.
Time
Ref. displacement deactivated Ref. displacement deactivated
Low temp. alarm limit
Cut out
Differential
High alarm limit
High temp. alarm limit due to thermostat ref. replacement
Alarm limit also changes
(similar to high alarm limit)
Ref. displacement activated
Night mode
Night mode helps to reduce cooling load and thereby power consumption during non-business hours i.e., Night
time. The thermostat set point will be oset by a xed value during night mode keeping alarm limits same.
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Electronic refrigeration control, type ERC 21X

Figure 8: Night mode
Fan cycling during compressor OFF cycle
During compressor OFF cycle controller will run the fan with dened duty cycle to maintain uniform temperature
and delay the need of compressor switching ON.
Figure 9: Fan cycle
Danfoss 80G8475
Thermostat cut in
Thermostat cut out
Fan
Compressor
Fan ON
cycle
Fan OFF
cycle
Cabinet air temp.
Defrost on Demand
This feature records the evaporator temperature when it is clean and constantly monitors the compares that at
every compressor cut outs. If the evaporator temperature goes below the recorded temperature by the value set in
parameter d30 before the congured defrost interval, it will trigger defrost immediately.
• This function can only be used in 1:1 systems.
• This function is disabled when the parameter “d30” is set to 20.
• Defrost on demand is triggered only if the time since the last defrost session has ended is greater than ¼ of the
defrost interval or 2 hours whichever is lesser.
• Defrost doesn’t start by this method during the following scenarios.
◦Pull down mode
◦Night mode
◦Main switch in DI or main switch in Menu is in OFF position
◦Manual control mode
◦Evaporator temperature greater than 0 °C.
Electronic refrigeration control, type ERC 21X
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