Introduction
The EKC 347 is a PI liquid level controller designed for regulating refrigerant levels in various systems, including pump packages, separators, economizers, condensers, and intermediate coolers. It measures the refrigerant liquid level via a signal transmitter and uses a user-selected program to control a valve, ensuring the level matches the specified setpoint.
Valve Compatibility
The EKC 347 supports liquid level control with the following valve types:
- Type ICM motorized modulating valve with ICAD motor actuator
- Types AKV or AKVA pulse width modulating expansion valve
- Solenoid valve for on-off control
Features
- Generates alarms when user-programmed limits are exceeded.
- Provides 3 relay outputs for upper and lower level limits and for alarm level.
- Accepts an analog input signal to offset the liquid level setpoint.
- Controls liquid level on either the high or low pressure side of the system.
- Supports master-slave configurations for controlling up to 3 AKV/A valves with distributed opening degrees when AKV/A is selected.
- Offers manual control of output.
- Allows limiting minimum and maximum valve opening degrees.
Ordering Information
| Type | Function | Code No. |
|---|---|---|
| EKC 347 | Liquid level controller | 084B7067 |
Application Examples
Pump package (liquid separator)
Modulating control of injection provides more stable liquid level and more stable suction pressure.
Receiver or condenser
The control system's short reaction time makes it well-suited for high pressure float systems with small refrigerant charges.
Multiple AKV/A control in master-slave configuration
Diagram illustrating how multiple controllers can be used to control multiple AKV/A valves in a master-slave setup, showing connections between controllers and valves.
Operating the EKC 347
The Display
The EKC 347 features a three-character digital display and four status LEDs (Light Emitting Diodes) to the left of the numerals. Two push buttons are located to the right of the display. By default, the display shows the liquid level percentage. User programming allows the valve's opening degree to be displayed instead. Pressing the lower pushbutton toggles between liquid level percentage and valve opening percentage for 5 seconds.
Front Panel LEDs
The upper LED indicates a signal is being sent to open a pulse-width modulated valve (AKV/A) or a solenoid valve for on-off applications. This LED has no function when using the EKC 347 with an ICM/ICAD motorized valve.
The three lower LEDs indicate alarms or regulation errors. The meanings are as follows:
- Opening signal to valve: Indicated by the top LED.
- Indication of upper level limit: Indicated by one of the lower LEDs.
- Indication of lower level limit: Indicated by one of the lower LEDs.
- Indication of alarm level: Indicated by one of the lower LEDs.
If an alarm or error occurs, all three lower LEDs will flash. Pressing the upper button for 1 second displays the alarm code (e.g., 'A3') or error code. If both an alarm and an error are present, only the error code is shown. Displaying an alarm code will cause alarm relay A3 to cut out.
The table below lists error (E), alarm (A), and status (S) codes:
| Code | Description |
|---|---|
| E1 | Errors in the controller |
| E12 | Analog input value on terminals 19 & 21 or 20 & 21 is out of range |
| E21 | No signal from the liquid level sensor, or the signal value is out of range* |
| E22 | Valve position feedback on terminals 17 & 18 is out of range |
| A1 | High level alarm A1 has been detected |
| A2 | Low level alarm A2 has been detected |
| A3 | Additional level alarm A3 has been detected |
| S10 | Level regulation stopped by internal (parameter r12) or external (terminals 1 &2) start-stop |
| S12 | High or low level alarm has been detected when not using alarm A3 as a common alarm |
*If the liquid level sensor signal is lost, the controller will force the valve fully closed (if parameter n35 is 0) or fully open (if parameter n35 is 1). If maximum or minimum valve opening degrees are set (parameters n32, n33), the valve will be forced to those limits.
To view or change liquid level set point:
Visual guide showing button presses for setpoint adjustment: Press both buttons simultaneously to enter change mode; press the upper button to raise the setpoint; press the lower button to lower the setpoint; press both buttons simultaneously to save the change.
To change a parameter setting:
Visual guide for parameter adjustment: Press the upper button for 5 seconds to access the parameter menu; use upper/lower buttons to scroll; press both buttons simultaneously to enter change mode for a selected parameter; press the upper button to increase a setting; press the lower button to decrease a setting; press both buttons simultaneously to save the new setting and return to the parameter menu. The controller exits the menu after 18-20 seconds of inactivity.
To reset to factory default values:
- Remove the supply voltage to the EKC 347.
- While pressing both buttons simultaneously, restore power. Factory settings will be restored.
Regulation Examples
Regulation Example 1: Programming the EKC 347 for use with ICM Motorized valve with ICAD motor-actuator
The EKC 347 is factory-configured for low-pressure side regulation using an ICM motorized valve with ICAD motor-actuator, a 4-20 mA signal, and an AKS 41U level probe. Key settings to adjust for most applications include:
- Setting the user-defined liquid level percentage (accessed by pressing both buttons simultaneously when the controller is in normal display mode).
- Setting user-defined parameter n04 (P-band), which defines the liquid level range around the setpoint for regulation.
- Changing parameter o12 to 1 for 60 Hz power supply (if applicable).
- Setting user-defined alarm parameters.
Diagram showing liquid level percentage versus valve opening percentage, illustrating the P-band (n04) as a range around the setpoint for regulation.
Regulation Example 2: Solenoid on-off control on low pressure side of the system
For this application, the following settings are required:
- Parameter o09: Set to 3 or 4 based on the output on terminals 2 and 5.
- Enter the user-defined setpoint (liquid level %).
- Set the user-defined differential (dead band) using parameter n34, which defines the liquid level range around the setpoint for valve operation.
- Set the P-band (parameter n04) to 0% (OFF).
- Set the controller frequency to 60 Hz (parameter o12 = 1).
- Configure user-defined alarm parameters.
Diagram illustrating solenoid output (24Vac) from terminals 23 and 24, showing the valve opening and closing based on the liquid level relative to the setpoint and dead band (n34).
Settings and Parameters
Level control settings
| Description of setting | Parameter | Minimum | Maximum | Factory setting |
|---|---|---|---|---|
| Liquid level setpoint | - | 0 (%) | 100 (%) | 50 (%) |
| % Displacement of liquid level setpoint with an analog input to the EKC 347 from a PLC or other device | r06 | -100 (%) | 100 (%) | 0% |
| Start-Stop regulation: Allows stopping controller regulation; valve closes when OFF. Works with terminals 1 & 2. Regulation stops if terminals 1 & 2 are not connected or r12 is OFF. | r12 | 0 (OFF) | 1 (ON) | 1 (ON) |
Alarm parameters
| Description of setting | Parameter | Minimum | Maximum | Factory setting |
|---|---|---|---|---|
| High level alarm relay A1: Relay (terminals 9 & 10) cuts in when liquid level exceeds parameter A01 for time A03. Always cut out during power interruption. | A01 | 0 (%) | 100 (%) | 85 (%) |
| Low level alarm relay A2: Relay (terminals 8 & 10) cuts in/out when liquid level is below parameter A02 for time A15. Parameter A18 determines cut-in/out. Always cut out during power interruption. | A02 | 0 (%) | 1 | 15 (%) |
| Time delay for high level alarm relay A1 | A03 | 0 (sec) | 999 (sec) | 10 (sec) |
| Time delay for low level alarm relay A2 | A15 | 0 (sec) | 999 (sec) | 20 (sec) |
| Additional alarm relay A3: Can be used for additional high/low level alarm (cut-in if level exceeds parameter A16 for time A17). Parameter A18 determines high/low. Can also be a common alarm (parameter A19). Always cut in during power interruption or if level sensor signal is lost. | A16 | 0 (%) | 100 (%) | 50 (%) |
| Time delay for additional alarm A3 (in seconds) | A17 | 0 (sec) | 999 (sec) | 0 (sec) |
| Defining the switching functions of alarms A2 and A3: | A18 | 0 | 3 | 0 |
| Setting 0: A2 cuts in under alarm conditions; A3 is a high liquid level alarm. | ||||
| Setting 1: A2 cuts in under alarm conditions; A3 is a low liquid level alarm. | ||||
| Setting 2: A2 cuts out under alarm conditions; A3 is a high liquid level alarm. | ||||
| Setting 3: A2 cuts out under alarm conditions; A3 is a low liquid level alarm. | ||||
| Additional alarm A3 used as a common alarm: | A19 | 0 | 1 | 0 |
| Setting 0: Alarm relay A3 is a common alarm (cuts in for A1, A2, or A3). | ||||
| Setting 1: Alarm relay A3 cuts in only for an A3 alarm. |
Regulating parameters
| Description of setting | Parameter | Minimum | Maximum | Factory setting |
|---|---|---|---|---|
| P-band (regulating range around setpoint): Regulating range around the liquid level setpoint. Factory setting of 30% provides a range of +/-15% around the setpoint. For ON-OFF control with a solenoid valve, set to 0% (OFF). | n04 | 0 (OFF) | 200 (%) | 30 (%) |
| Integration time Tn: Decreasing integration time results in faster regulation but more fluctuation in valve opening. | n05 | 60 (sec) | 600 (sec) (OFF) | 400 (sec) |
| Period time for AKV and AKVA pulse valves: Determines the control period length. Valve is opened for a percentage of each period. | n13 | 3 (sec) | 10 (sec) | 6 (sec) |
| Maximum opening degree | n32 | 0 (%) | 100 (%) | 100 (%) |
| Minimum opening degree | n33 | 0 (%) | 100 (%) | 0 (%) |
| Dead band or differential setting for ON-OFF control with solenoid valve: Prevents excessive control action near the setpoint. Active only for ICM valve with ICAD motor-actuator. Eliminates excessive valve movement by requiring changes greater than the dead band. Differential setting for ON-OFF control is active when parameter n04=0. | n34 | 2 (%) | 25 (%) | 2 (%) |
| Definition of regulating principle: | n35 | 0 (LOW) | 1 (HIGH) | 0 (LOW) |
| Setting 0 (LOW): Regulation on the low pressure side; valve closes on rising liquid level. | ||||
| Setting 1 (HIGH): Regulation on the high pressure side; valve opens on rising liquid level. |
Miscellaneous parameters
| Description of setting | Parameter | Minimum | Maximum | Factory setting |
|---|---|---|---|---|
| Define valve and AO (analog output) signal: Configures the controller for different valve types (ICM/ICAD, AKV/A, solenoid) and analog output (AO) signal types (4-20 mA, 0-20 mA) for communications or remote monitoring. Also includes settings for master-slave configurations of AKV/A valves. | o09 | 1 | 17 | 1 |
| Input signal for offsetting the liquid level setpoint: Defines the analog input (terminals 19 & 21 or 20 & 21) used to offset the liquid level setpoint. Options include No signal, 4-20 mA, 0-20 mA, 2-10 V, 0-10 V. Offset is proportional to the input signal and parameter r06. | o10 | 0 | 4 | 0 |
| Frequency of 24 Vac power source: Must match the power supply frequency (50 Hz or 60 Hz). | o12 | 0 (50 Hz) | 1 (60 Hz) | 0 (50 Hz) |
| Selection of normal display contents and AO: Determines if the normal display shows liquid level or valve opening degree. Other value can be displayed for 5 seconds by pressing the lower pushbutton. AO on terminals 1 & 2 corresponds to the normal display when not using ICM/ICAD or AKV/A as MASTER. | o17 | 0 | 1 | 0 |
| Manual control of outputs: Allows manual switching of individual relay outputs when regulation is stopped. Options for OFF, manual ON for upper level relay, lower level relay, AKV/A or Solenoid output, and additional alarm relay. | o18 | 0 (OFF) | 4 | 0 |
| Input signal from liquid level sensor: Defines the liquid level input signal on terminals 14 & 16 or 15 & 16. Options: No signal, Current signal (4-20 mA, e.g., AKS 41U probe), or Voltage signal (range set by o32/o33). For AKV/A master-slave, master signal must be 4-20 mA, and slaves must also be set to 1 even if voltage input is used. | o31 | 0 | 2 | 1 |
| Voltage signal minimum value (only used if parameter o31 = 2) | o32 | 0.0 (V) | 4.9 (V) | 4.0 (V) |
| Voltage signal maximum value (only used if parameter o31 = 2) | o33 | 5.0 (V) | 10.0 (V) | 6.0 (V) |
| Valve position feedback: Uses ICM/ICAD position feedback signal (terminals 17 & 18) to determine displayed opening degree. 0: Feedback not used. 1: 4-20 mA feedback from ICM/ICAD connected. 2: Obsolete. | o34 | 0 | 2 | 0 |
| Controller's address: For networks with data communications, sets the controller's address (01-60) to match the master gateway. | o03 | 0 | 60 | 0 |
| Service pin message: Sends the address to the gateway when set to ON. Automatically reverts to OFF after a few seconds. | o04 | 0 (OFF) | 1 (ON) | 0 (OFF) |
| Language: Sets the output language for the AKM program. Parameter o04 must be set to 1 (ON) after changing language for the setting to take effect. Options: English, German, French, Danish, Spanish, Italian, Swedish. | o11 | 0 | 6 | 0 |
Troubleshooting Parameters
The following parameters are for viewing service information:
| Description of parameter to view | Parameter | Units |
|---|---|---|
| Liquid level (actual) | u01 | % |
| Liquid level setpoint, including analog input offset (parameter r06) | u02 | % |
| Analog input signal current (terminals 19 & 21). Used for offsetting the liquid level setpoint. | u06 | mA |
| Analog input signal voltage (terminals 20 & 21). Used for offsetting the liquid level setpoint. | u07 | V |
| Analog output signal current terminals (2 & 5) | u08 | mA |
| Digital input status. Combination of parameter r12 and terminals 1 &2. | u10 | ON-OFF |
| Valve opening degree | u24 | % |
| Level sensor signal current (terminals 15 & 16) | u30 | mA |
| Level sensor signal voltage (terminals 14 & 16) | u31 | V |
| Valve position current feedback signal from ICM/ICAD (4-20 mA) | u32 | mA |
| Valve position feedback signal from ICM/ICAD converted to % | u33 | % |
Technical Data
The supply voltage is galvanically isolated from input and output signals, but input and output signals are not isolated from each other.
- Supply voltage: 24 V ac ± 15%, 50-60 Hz. 60 VA maximum (5 VA for controller, 55 VA for solenoid coil or AKV/A pulse valve).
- Input signals: Liquid level sensor (4-20 mA or 0-10 V), ICM/ICAD valve position feedback (4-20 mA only), Digital input (terminals 1 & 2 for start-stop), Signal for setpoint offset (4-20 mA, 0-20 mA, 2-10 V, or 0-10 V).
- 3 Relay Outputs: SPST, AC-1: 4A (ohmic), AC-15: 3A (Inductive).
- Current Output (terminals 2 & 5): 0-20 mA or 4-20 mA, 500 Ω maximum load.
- Ambient temperature: Operation: +14 to +131°F (-10 to 55°C). Transport/Storage: -40 to 158°F (-40 to 70°C).
- Approvals: Complies with EU Low Voltage Directive and EMC demands. Tested according to EN 60730-1, EN 60730-2-9, EN 50081-1, and EN 50082-2.
Diagram showing physical dimensions: 54 mm (width), 72 mm (height), 45 mm (depth). Mounting: DIN rail. Enclosure: IP 20. Weight: 300 g (0.66 lbs). Display: 3-digit LED. Terminals: Max 2.5 mm² multicore.
Technical Data: Terminal Functions
| Terminal pairs | Description | Terminal pairs | Description |
|---|---|---|---|
| 1-2 | Switch function for start-stop of regulation. If no connection, controller signals valve to close. Short terminals with jumper if not using a switch. | 14-16 | Voltage input from level sensor |
| 15-16 | Current input from level sensor | ||
| 2-5 | Current output for ICM/ICAD valve control. Also used for remote monitoring when ICM/ICAD is not used (see parameter o09). | 17-18 | Optional current input from 4-20 mA ICM/ICAD valve position feedback. |
| 8-10 | Low level relay A2. Relay can be set to cut in or out when level is lower than set limit (parameter A02). Cut out during any power interruption. | 19-21 | Optional current input from PLC etc., for offsetting liquid level setpoint. |
| 9-10 | High level relay A1. Relay cuts in when liquid level is higher than set limit (parameter A01). Cut out during any power interruption. | 20-21 | Optional voltage input from PLC etc., for offsetting liquid level setpoint. |
| 12-13 | Additional relay A3. Can be set to cut in on rising or falling liquid level, or as a common alarm (A1, A2, or A3) via parameters A16, A18, A19. Cuts in during power interruption or if level sensor signal is lost. | 23-24 | Maximum 20W. 24 Vac output for solenoid valve on-off control, or AKV/A pulse width modulation control. Can also be for a 24 Vac relay to control a solenoid valve (not AKVA). |
| 25-26 | Supply voltage 24 Vac, 60 VA maximum load when using 24 Vac output (terminals 23 & 24). | 3-4 | Optional data communication connection. Valid only with a special data communication module. |
Wiring diagram illustrating connections for power supply (24V AC/DC), level probe (AKS 41), ICM/ICAD valve feedback, AKV/AKVA/solenoid valve control, and alarm relays, showing terminal assignments.
Field Settings List
Miscellaneous Parameters
| Description of setting | Parameter | Min | Max | Factory setting | Field Setting |
|---|---|---|---|---|---|
| Define valve and AO (analog output) signal: Configures controller for valve types (ICM/ICAD, AKV/A, solenoid) and AO signal types (4-20 mA, 0-20 mA) for communications or remote monitoring. Includes master-slave settings for AKV/A valves. | o09 | 1 | 17 | 1 | |
| Input signal for offsetting the liquid level setpoint: Defines analog input (terminals 19 & 21 or 20 & 21) for setpoint offset. Options: No signal, 4-20 mA, 0-20 mA, 2-10 V, 0-10 V. Offset is proportional to input and parameter r06. | o10 | 0 | 4 | 0 | |
| Frequency of 24 Vac power source: Must match supply frequency (50 Hz or 60 Hz). | o12 | 0 (50 Hz) | 1 (60 Hz) | 0 (50 Hz) | |
| Selection of normal display contents and AO: Sets normal display to liquid level or valve opening degree. Other value viewable for 5 sec by lower button. AO on terminals 1 & 2 corresponds to normal display if ICM/ICAD or AKV/A not MASTER. | o17 | 0 | 1 | 0 | |
| Input signal from liquid level sensor: Defines input signal on terminals 14 & 16 or 15 & 16. Options: No signal, Current (4-20 mA), Voltage. For AKV/A master-slave, master signal must be 4-20 mA, slaves must be set to 1. | o31 | 0 | 2 | 1 | |
| Voltage signal minimum value (only used if parameter o31 = 2) | o32 | 0.0 (V) | 4.9 (V) | 4.0 (V) | |
| Voltage signal maximum value (only used if parameter o31 = 2) | o33 | 5.0 (V) | 10.0 (V) | 6.0 (V) | |
| Valve position feedback: Uses ICM/ICAD position feedback signal (terminals 17 & 18) for displayed opening degree. 0: Not used. 1: 4-20 mA feedback connected. 2: Obsolete. | o34 | 0 | 2 | 0 |
Regulating Parameters
| Description of setting | Parameter | Min | Max | Factory setting | Field Setting |
|---|---|---|---|---|---|
| P-band (regulating range around setpoint): Range around setpoint for regulation. Factory 30% gives +/-15% range. For ON-OFF control with solenoid valve, set to 0% (OFF). | n04 | 0 (OFF) | 200 (%) | 30 (%) | |
| Integration time Tn: Decreasing integration time increases regulation speed but also valve opening fluctuation. | n05 | 60 (sec) | 600 (sec) (OFF) | 400 (sec) | |
| Period time for AKV and AKVA pulse valves: Control period length. Valve opens for a percentage of each period. | n13 | 3 (sec) | 10 (sec) | 6 (sec) | |
| Maximum opening degree | n32 | 0 (%) | 100 (%) | 100 (%) | |
| Minimum opening degree | n33 | 0 (%) | 100 (%) | 0 (%) | |
| Dead band or differential setting for ON-OFF control with solenoid valve: Prevents excessive control action near setpoint. Active for ICM valve with ICAD motor-actuator. Eliminates excessive valve movement by requiring changes greater than dead band. Differential setting for ON-OFF control is active when n04=0. | n34 | 2 (%) | 25 (%) | 2 (%) | |
| Definition of regulating principle: Setting 0 (LOW): Regulation on low pressure side; valve closes on rising level. Setting 1 (HIGH): Regulation on high pressure side; valve opens on rising level. | n35 | 0 (LOW) | 1 (HIGH) | 0 (LOW) |
Alarm Parameters
| Description of setting | Parameter | Min | Max | Factory setting | Field Setting |
|---|---|---|---|---|---|
| High level alarm relay A1 (%): Relay (terminals 9 & 10) cuts in when level exceeds parameter A01 for time A03. Always cut out during power interruption. | A01 | 0 (%) | 100 (%) | 85 (%) | |
| Low level alarm relay A2 (%): Relay (terminals 8 & 10) cuts in/out when level is below parameter A02 for time A15. Parameter A18 determines cut-in/out. Always cut out during power interruption. | A02 | 0 (%) | 100 (%) | 15 (%) | |
| Time delay for high level alarm relay A1 | A03 | 0 (sec) | 999 (sec) | 10 (sec) | |
| Time delay for low level alarm relay A2 | A15 | 0 (sec) | 999 (sec) | 20 (sec) | |
| Additional alarm relay A3: Can be used for additional high/low level alarm (cut-in if level exceeds parameter A16 for time A17). Parameter A18 determines high/low. Can also be a common alarm (parameter A19). Always cut in during power interruption or if level sensor signal is lost. | A16 | 0 (%) | 100 (%) | 50 (%) | |
| Time delay for additional alarm A3 (in seconds) | A17 | 0 (sec) | 999 (sec) | 0 (sec) | |
| Defining the switching functions of alarms A2 and A3: Setting 0: A2 cuts in; A3 is high level alarm. Setting 1: A2 cuts in; A3 is low level alarm. Setting 2: A2 cuts out; A3 is high level alarm. Setting 3: A2 cuts out; A3 is low level alarm. | A18 | 0 | 3 | 0 | |
| Additional alarm A3 used as a common alarm: Setting 0: A3 is common alarm (cuts in for A1, A2, or A3). Setting 1: A3 cuts in only for an A3 alarm. | A19 | 0 | 1 | 0 |
