The EMLI Electromagnetic Level Measurement with Suspended Sensors
EMLI System Description
The EMLI™ (Electro Magnetic Level Indication) system utilizes state-of-the-art technology in the measurement and detection of liquid metal levels. The basic EMLI system architecture consists of a MANAGEMENT UNIT, a CONTROL UNIT and a PREAMPLIFIER UNIT. In multiple system applications, one MANAGEMENT UNIT can monitor up to eight (8) CONTROL UNITS.
The MANAGEMENT UNIT is used to monitor the system, log data, and for set-up and troubleshooting. If enabled the system can be remotely evaluated through the MANAGEMENT UNIT via an Internet connection.
The CONTROL UNIT is the heart of the system. It generates the transmitter signal and receives and evaluates the measurement signal.
The PREAMPLIFIER UNIT increases the level of the measurement signal before it is fed to the CONTROL UNIT
EMLI - Mold Level Measurement System
The EMLI mold level measurement system with suspended sensor consists of a state-of-the-art electronics packaged combined with a custom designed and steel mill proven electromagnetic metal level sensor.
The sensor is mounted on a removable arm that is positioned in such a manner that the actual sensor head is suspended over the liquid metal pool. The sensor arms can be manually operated or automated.
This arrangement allows for the easy removal and insertion of the sensor, even during casting.
The EMLI suspended sensor is basically a balanced coil that is suspended over the liquid pool of metal. The proprietary coil design is such that the measurement area is concentrated to a narrow area below the sensor. This design minimizes the influence of materials above the sensor and the influence of the mold side walls.
The sensor consists of three coils, one transmitter coil and two receiver coils. An excitation signal from the EMLI™ electronic unit is applied to the transmitter coil. The receiver coils are connected in such a manner that when there is no metal present in the sensors' measurement field, the output of the sensor is approximately zero. This is considered to be the 'balanced' condition.
When metal in introduced into the sensor's measurement field, the metal has a greater effect on one of the receiver coils than on the other. This causes an output from the sensor and the sensor is said to be 'unbalanced'. This effect is used by the EMLI™ electronic unit to generate a signal that is proportional to the level of metal in the mold.
The EMLI mold level measurement system with suspended sensors offers the following benefits: