The EWLS electronic level switch uses conductivity measurement for steam boilers and other conductive-liquid applications. It comprises a water column with 1–4 probes, a measuring unit, a control unit with local LED indication and connection cables. Probe spacing and contact assignments can be configured for the application.

Both measuring and control units contain two independent electronic circuits with their own processors and regular self-tests. Redundant power supplies are standard. Local indication distinguishes water, steam, normal operation and system faults. Configurable SPDT contacts and time delays are provided, together with dedicated fault and water-level alarm contacts.

The 4–20 mA output changes in proportion to the number of immersed probes and falls to 2 mA on a fault; the listed maximum load is 500 Ω. Configuration uses four buttons and a backlit two-line, 16-character LCD. Diagnostics include power, probe, cable, short-circuit and board faults. Options include EL65/EL60 probes and a DU3 remote display. Confirm enclosure protection, materials and the required boiler approvals for the selected assembly.