Gestra NRG17-50 Level Probe 1500mm
The level electrodes NRG 1...-50 are used in conjunction with level switch NRS 1-50 as water level limiters for steam boiler plants and (pressurised) hot water installations.

Water level limiters switch off the heating when the water level falls below the set minimum level (low water).

When the water falls below the low level, the electrode is exposed, triggering a low-level alarm in the level switch NRS 1-50. This switchpoint, “Low water level (LW)” is determined by the length of the electrode tip. The electrode operation utilises the conductive measuring principle using the electrical conductivity of the water for signalling water level.

The self-monitoring function ensures an alarm will be triggered if the electrode insulation is contaminated, has leaked, and/or if there is a malfunction in the electrical connection.

The level electrode is for installation inside steam boilers, vessels or inlet lines of hot-water systems. The protection tube provided on-site ensures the function.

One level electrode NRS 1...-50 can be installed alongside one GESTRA level electrode, one level switch or transmitter for water level control and a low-level alarm in one single protection tube or level pot.

If the level electrode installation is in a level pot outside the boiler, ensure that the connecting lines are cleaned and rinsed regularly. In addition, the logic unit SRL is a requirement to monitor the purging times and the purging sequence.

If the connecting lines for steam ≥ 40mm and water ≥ 100mm the installation is considered “inside”. In this case, the purging process does require monitoring.