In hot‑dip coating plants, steel strip is continuously coated with molten zinc, zinc alloys or aluminium alloys, a process that places considerable demands on equipment accuracy and stability. Inductive eddy current sensors play a crucial role within the electromagnetic stabilisation systems used to control strip behaviour during coating. With strip running at high speeds, vibration becomes a significant challenge, and market leader EMG relies on between 10 and 16
Micro‑Epsilon EU40 inductive sensors in each stabilisation unit to minimise movement and ensure a stable coating process.
Throughout the coating line, these sensors measure strip vibration as precise distance values without any physical contact. The data is fed directly to the EMG electromagnetic stabilisation system, enabling continuous monitoring and effective vibration suppression. Designed specifically for harsh industrial environments, the EU40 sensors withstand elevated temperatures as well as chemical and mechanical stresses.
Their 40mm measuring range provides sufficient scope for monitoring the dynamic movement of the strip, and they are operated via the compact eddyNCDT 3020 industrial controller in a dedicated EMG‑specific configuration (DT3029/EMG). This controller is equally robust, offering IP67 protection and a temperature resistance of up to 105°C, allowing it to be fully integrated into the stabilisation unit.
High precisionStrong EMC immunity ensures that the sensor‑controller combination maintains stable output even in close proximity to powerful electromagnets. With a short 1m cable and excellent temperature stability, the system achieves high precision, delivering a consistent analogue current signal to a control unit up to 50m away.
The eddyNCDT 3020 system is engineered for operation in extreme industrial conditions, withstanding ambient temperatures up to 200°C (105°C for the controller and 200°C for the sensor). Its high measurement rate of 80kSa/s allows it to capture fast movements with accuracy, while a 5kHz (-3 dB) cut‑off frequency reduces noise and contributes to stable, precise readings, achieving resolutions as fine as 40nm.
Each system is factory‑tuned to either ferromagnetic or non‑ferromagnetic materials, depending on application requirements. With its compact IP67‑rated housing (102 × 53 × 30mm) and flexible configuration options, the system is well suited to demanding industrial environments and to direct installation within machine assemblies.