501 501
501 Electrode Base

The Conductivity Level Switch type 501 is a simple level system for controlling levels.

The system includes a transmitter for DIN-rail mounting and various level electrodes.

  • The 501 level relay with electrodes are most commonly used as a simple safety device providing level alarms in case of water leaking on floors with no constant monitoring.
  • 501 provides an alarm signal based on the conductivity in the liquid thereby securing the important electronics or non-submersible pumps.
  • Some waste water plant also uses 501 as an additional security device providing alarm signals or starting pumps based on the 2-4 electrodes in individually adapted lengths


Supply 115/230 V AC ±10%, app. 4VA
Sensitivity Min.: 100 mA Max.: 1mA
Relay Output Voltage-free switch, max. 250V, 4A resistive, 1A inductive



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