Introduction
The EKE 347 controller is designed for liquid level control in various industrial applications, including pump tanks, separators, intercoolers, economizers, condensers, and receivers. It continuously monitors liquid levels and automatically adjusts valve operations to maintain the desired setpoint.
The EKE 347 receives measured values from a liquid level transmitter. By comparing these values to customer-defined setpoints, it operates valves to control inflow or outflow, thereby maintaining the desired liquid level.
Key Features
- Liquid Level Control: Precise control of liquid levels.
- Alarms: Generates alarms when setpoints are exceeded (high or low limits).
- Relay Outputs: Three configurable relay outputs for high/low limit and alarm signals.
- Setup Wizard: User-friendly initial setup wizard for easy configuration.
- Control Modes: Supports PI control, low-side or high-side control.
- Master/Slave Configuration: Enables master/slave systems to control up to three expansion valves (AKV/A).
- Manual Control: Allows manual adjustment of output.
- Angle Limitation: Configurable valve opening angle limits.
- Hysteresis: Adjustable hysteresis for ON/OFF operations.
- Access Levels: Three password-protected access levels for programming.
- Connectivity: Can connect to other EKE 347 controllers and supports remote display units.
- BUS Communication: Integrated support for CAN Bus (Danfoss internal) and MODBUS RTU RS485 for communication with PLCs and SCADA systems.
Applications
The EKE 347 is suitable for a range of applications:
- Pump Tank: Regulates inflow to maintain a stable liquid level and suction pressure.
- Evaporator (Full): Maintains consistent liquid levels even under fluctuating load conditions, utilizing the wide capacity range of the control valve.
- Intercooler: Monitors liquid levels across the entire measurement range, enabling safety functions related to maximum permissible levels.
- Receiver/Condenser: Ideal for high-pressure float systems with low refrigerant charge due to its fast response time.
System Components and Communication
Signal Transmitters
The controller can be used with microwave inductive level sensors like the AKS 4100/4100U, which offer precise measurement across a wide temperature range.
Expansion Valves
The EKE 347 supports two types of Danfoss expansion valves:
- ICM: A direct-acting electric valve controlled by an ICAD unit.
- AKV/A: A pulse-width modulated expansion valve.
An analog input is provided for feedback from the ICM's opening angle.
MODBUS Communication
Equipped with standard RS485 MODBUS-RTU communication, the EKE 347 can interface with PLCs and other third-party devices. This allows for parameter reading and writing, enabling remote operation, monitoring, and data collection via SCADA systems.
Remote Display Option
A panel-mountable remote display (MMIGRS2) can be connected. This display provides a comprehensive overview and access to all EKE 347 controllers connected via the internal Danfoss CAN bus.
Control Panel and Display
The control panel features four buttons: Enter (▶️), Up (⬆️), Down (⬇️), and Back (⬅️). The home screen displays a system overview. The display shows the controller name, measured liquid level, controller mode (On/Off), valve opening angle, and status of low/high level alarms. An audible alarm icon (bell ?) will flash when an alarm is active.
Navigation allows access to the Status Menu (short press of Enter) and the Setup & Service Menu (long press of Enter), which requires password authentication.
Menus
Status Menu (Open Menu)
This menu is accessible to all users and displays information such as:
- Setpoint
- Active Alarms
- Detailed Status (Controller state, measured values, digital input status, etc.)
- Controller Info (Type, product name, software/BIOS version, address, serial number, etc.)
- QR Code
Setup & Service Menu
This menu requires a password for access and is divided into three levels:
- Commissioning: Full access to all parameters, including re-running the setup wizard.
- Service: Access for service technicians with restricted permissions.
- Normal: Daily use level with limited modification capabilities.
Parameters and Configuration
The EKE 347 offers extensive configuration options accessible via the Setup & Service menu. These include:
- Alarm Setup: Configuration of low/high level limits, delays, hysteresis, and common alarms.
- Control: Settings for control method (On/Off, P, PI), proportional band, integral time, dead band, and valve control parameters.
- Display: Language selection, output display mode (level/OD), login timeout, backlight settings, and password management.
- IO Configuration: Setup for system configuration (e.g., ICAD, AKV/A), signal inputs (voltage/current), and valve position feedback.
- Communication: Configuration for MODBUS (ID, speed, mode, mapping) and CAN Bus (ID, speed).
Detailed parameter tables are available in the documentation, listing each parameter, its range, default value, and Modbus PNU.
Wiring and Connections
The controller features screw terminals for various connections:
- Supply Voltage: 24V AC/DC.
- Level Transmitter Input: For sensors like AKS 4100/4100U.
- Expansion Valve Control: Outputs for controlling ICM or AKV/A valves.
- Relay Outputs: Configurable for common alarm, high/low level limits.
- Digital Inputs: For external signals like start/stop or alarms.
- Communication Ports: RJ45 for CAN bus and screw terminals for MODBUS RTU.
Detailed wiring diagrams are provided for different configurations, including high-level alarms, low-level alarms, and ON/OFF operation. These diagrams illustrate the physical connections between the EKE 347, sensors (e.g., AKS 4100/4100U, AKS 41), expansion valves (ICM, AKV/A), and other system components.
Dimensions: The controller has dimensions of approximately 70mm (width) x 110mm (height) x 63mm (depth), with a 5mm projection for mounting.
Master/Slave and Multi-Valve Systems
The EKE 347 supports master/slave configurations to control multiple expansion valves (up to three) simultaneously. This is configured through the "Multi-valve system setup" and "System connection pattern" (parallel or serial) options in the IO configuration menu.
In a multi-valve system, the master controller displays system status and total opening angle, while slave controllers show their individual status.
Remote Display and Communication Examples
Various examples illustrate the connection of the EKE 347 with sensors, expansion valves, and remote displays via CAN bus and MODBUS.
Error Code ERR31: Indicates a communication failure with the external display (MMIGRS2). Troubleshooting involves checking terminations, display software version, and specific menu settings (MCX selection, COM selection, Start up mode, CAN baudrate/Node ID).
Technical Specifications
| Parameter | Range | Default Value | Unit | Modbus PNU |
|---|---|---|---|---|
| Main Switch | 0-1 | 0 | 3001 | |
| Liquid Level Setpoint | 0-100% | 50 | % | 3002 |
| Operating Mode | 0-2 | 0 | 3003 | |
| Low Level Limit | 0-100% | 15 | % | 3004 |
| High Level Limit | 0-100% | 85 | % | 3005 |
| Liquid Level Alarm Mode | 0-1 | 0 | 3006 | |
| Low Level Alarm Delay | 0-999 | 10 | sec | 3007 |
| High Level Alarm Delay | 0-999 | 50 | sec | 3008 |
| Low Level Hysteresis | 0-20% | 3 | % | 3009 |
| High Level Hysteresis | 0-20% | 5 | % | 3010 |
| Common Alarm Function | 0-3 | 0 | 3011 | |
| Vibration Detection Band | 0-100% | 100 | % | 3012 |
| Vibration Detection Timeout | 2-30 | 20 | min | 3013 |
| Stop Mode Pump OFF | 0-1 | 0 | 3117 | |
| IO Low Level Limit | 0-100% | 5 | % | 3101 |
| IO High Level Limit | 0-100% | 95 | % | 3102 |
| IO Low Level Hysteresis | 0-20% | 3 | % | 3103 |
| IO High Level Hysteresis | 0-20% | 3 | % | 3104 |
| IO Low Level Alarm Delay | 0-999 | 10 | sec | 3105 |
| IO High Level Alarm Delay | 0-999 | 50 | sec | 3106 |
| IO Level Limit | 0-100% | 50 | % | 3107 |
| IO Level Alarm Delay | 0-999 | 10 | sec | 3108 |
| IO Level Hysteresis | 0-20% | 3 | % | 3109 |
| IO Level Change | 0-1 | 0 | 3110 | |
| Control Method | 0-2 | 2 | 3014 | |
| Control Type | 0-1 | 0 | 3015 | |
| Proportional Band | 5-200% | 30.0 | % | 3016 |
| Integral Time Tn | 60-600 | 400 | sec | 3017 |
| Dead Band | 0-25% | 2.0 | % | 3018 |
| Difference | 0.5-25% | 2 | % | 3019 |
| AKV/AKVA Period Time | 3-15 | 6 | sec | 3020 |
| Min OD | 0-99% | 0 | % | 3021 |
| Max OD | 1-100% | 100 | % | 3022 |
| Language | 0-0 | 0 | 3023 | |
| Output Display | 0-1 | 0 | 3024 | |
| Login Timeout | 1-120 | 10 | min | 3025 |
| Backlight Timeout | 0-120 | 2 | min | 3026 |
| Normal Password | 0-999 | 100 | 3027 | |
| Service Password | 0-999 | 200 | 3028 | |
| Commissioning Password | 0-999 | 300 | 3029 | |
| Contrast | 0-100% | 40 | % | 3030 |
| Brightness | 0-100% | 80 | % | 3031 |
| System Configuration | 0-4 | 0 | 3032 | |
| Liquid Signal Setup | 0-3 | 0 | 3033 | |
| Low Level Voltage | 0-10 | 0 | V | 3034 |
| High Level Voltage | 0-10 | 10 | V | 3035 |
| Low Level Current | 0-20 | 0 | mA | 3036 |
| High Level Current | 0-20 | 20 | mA | 3037 |
| Valve Position Setup | 0-2 | 0 | 3038 | |
| Valve Close Voltage | 0-10 | 0 | V | 3039 |
| Valve Open Voltage | 0-10 | 10 | V | 3040 |
| Valve Close Current | 0-20 | 0 | mA | 3041 |
| Valve Open Current | 0-20 | 20 | mA | 3042 |
| Common Alarm Setup | 0-3 | 1 | 3043 | |
| Multi-Valve System Setup | 0-4 | 0 | 3044 |
Ordering Information
| Type | Description | Code No. |
|---|---|---|
| EKE 347 | Level Controller | 080G5000 |
| MMIGRS2 | Remote Display, Panel, S | 080G0294 |
| - | Display Unit Cable, 1.5m, 1 pc. | 080G0075 |
| - | Display Unit Cable, 3m, 1 pc. | 080G0076 |
| - | Panel Mount Accessory for EKE / EKC | 027F0309 |
Data Specifications
| Parameter | Specification |
|---|---|
| Supply Voltage | 24V AC +/-20% 50/60 Hz or 24V DC +/-20% (Galvanically isolated from input/output signals) |
| Power Consumption | Controller: 15 VA / 10W; AKV or AKVA coil: 55 VA |
| Input Signal | Liquid Level: 4-20 mA or 0-10V; ICM Valve Feedback: ICAD 0/4-20 mA |
| Relay Output | 3-pole changeover (Low Level Alarm, High Level Alarm, Common Alarm/NC Solenoid Valve). Rated for 3 A GP, 250V AC. Max 240V AC or 24V AC/DC. |
| Current Output | 0-20 mA or 4-20 mA, max load 500 Ω. |
| Valve Connection | ICM - Current output; AKV/A - 24 VAC pulse-width modulated output. |
| Data Communication | MODBUS RTU: For system controller communication. RS485 with galvanic isolation (500V DC). CAN: For communication with other EKE controllers. |
| Modbus Commands | Read Holding Registers (0x03), Read Input Registers (0x04), Write Single Register (0x06), Diagnostics (0x08), Write Multiple Registers (0x10), Read Device ID (0x43). |
| Operating Environment | -20 to 55°C (operating), -30 to 80°C (storage). 90% relative humidity (non-condensing). Not affected by shock/vibration. |
| Enclosure | IP 20 / IP 40 (front panel mounting). |
| Weight | 193 g. |
| Mounting | DIN rail. |
| Display | LCD display. |
| Terminals | For 1.5 or 2.5 mm² multi-core cables. |
| Certifications | CE, EAC, cULus. Complies with EU Low Voltage Directive (EN 60730-1, EN 60730-2-9) and EMC requirements (EN61000-6-3, EN61000-6-2). UL File E31024. |
Disclaimer
While every effort has been made to ensure accuracy, Danfoss is not liable for any errors or omissions in this publication. Danfoss reserves the right to make changes to products without prior notice. Trademarks mentioned are the property of their respective owners.
