Product Description

GESTRA NRS 2-3 Level Switch

The GESTRA NRS 2-3 is a compact level switch designed for reliable level detection in conductive liquids. It is primarily used as a water level limiter (low water or high water alarm) in steam boilers and (pressurized) hot-water installations. Operating on the conductivity principle, it works in conjunction with GESTRA level electrodes (like the NRG 2x-x series) and a level controller/limiter unit (like the NRS 2-x series controller itself, which this product name often refers to as the *controller part* of the system). This system provides safety-tested level monitoring and meets stringent safety requirements, including SIL 3 certification according to IEC 61508.

Technical Specifications:

Supply Voltage Options: 24 V DC, 115 V AC (50/60 Hz), 230 V AC (50/60 Hz)
Power Consumption: Approx. 3 VA / 2 W
Output Contacts: 2 potential-free change-over contacts (High Level, Low Level)
Switching Capacity (Output Contacts): Max. 250 V AC / 4 A / 1000 VA; Min. 5 V / 10 mA
Ambient Temperature: -20 °C to +60 °C
Ingress Protection: IP 40 (Housing), IP 00 (Terminals) – Typically installed in a control cabinet
Mounting: DIN rail EN 60715 TH 35
Function: Level limiting (MIN/MAX alarm)
Approvals: SIL 3 (IEC 61508), TÜV type-approved (acc. to EN 12952 / EN 12953), various marine approvals possible
Associated Electrodes (Examples): NRG 26-1, NRG 211-1