Product Description

GESTRA NRS1-7 Level Switch

The GESTRA NRS 1-7 is an electronic level switch designed for signalling minimum or maximum liquid levels in conductive tanks, primarily used in steam boiler plants and (pressurized) hot water installations. It operates in conjunction with GESTRA level electrodes (e.g., NRG 1…-..) to detect when the water level reaches the electrode tip. Upon detection, the NRS 1-7 activates its output relay, providing a reliable limit signal for alarms or control system interlocks. It ensures safe operation by monitoring critical water levels.

Technical Specifications:

Supply Voltage: 230 V AC, 50-60 Hz (Standard); Options for 115 V AC, 24 V AC, 24 V DC available
Power Consumption: Approx. 3 VA
Sensitivity (Conductivity): Standard 10 µS/cm at 25 °C (Optional adjustable version NRS 1-7b: 0.5 – 1000 µS/cm)
Output Contact: 1 potential-free change-over contact
Max. Switching Capacity (Output): 250 V AC, 4 A, cos φ = 1; 30 V DC, 4 A
Indicators: LEDs for operational status (voltage ON) and switch status (level alarm)
Ambient Temperature Range: -20 °C to +60 °C
Housing Protection: IP 40
Terminal Protection: IP 20
Mounting: DIN rail EN 60715 TH 35
Approvals: TÜV type-approved acc. to VdTÜV ‘Water Level 100’, SIL 2 (acc. to IEC 61508)