Siemens Pressure Differential Sensor QBM81-...pdf

The Siemens Sygnalizator różnicy ciśnienia QBM81-.. is a pressure difference indicator used in ventilation and air conditioning installations. Key features include:

- Monitoring of pressure differences, underpressure, and overpressure
- Monitoring of filter air quality and airflow, as well as belt drive fan failures
- Simple installation with over 1 million switching cycles
- Precise adjustment and long-term stability

Available types (QBM81-3, QBM81-5, QBM81-10, QBM81-20, QBM81-50) cater to different pressure ranges (0.2-50 mbar, 20-5000 Pa, 0.08-20 inH2O).

The device consists of a housing, membrane, and steel support. It comes with FK-PZ3 cable set (2 channel adapters, 4 mounting screws, 2m long 5/8mm diameter cable). Additional cable sets (FK-PZ1, FK-PZ2) are available for precise measurements.

It operates by bending the membrane due to pressure difference, ensuring stable switching points. The indicator has a scale for precise adjustment.

Ordering information: Specify quantity, description, and type (e.g., 1 Sygnalizator różnicy ciśnienia QBM81-5). Additional equipment must be ordered separately.

Installation tips: Mount the device above pressure connection points, with cables having a slight slope to prevent condensate buildup. Allowable positions include any, but vertical is recommended. Longer cables may increase response time.

Operation tips: Adjust the set value using the knob under the cover. If mounted horizontally, adjust the switching point by ±11 Pa.

Disposal: Dispose of the device as electronic waste according to EU Directive 2012/19/EU.

Technical data: Strain gauge sensor, 24 V AC/DC or 250 V AC power supply, >1 million switching cycles, -30...75 °C (-30...85 °C for QBM81-50) operating temperature, IP54 protection rating, and compliance with EN 61326-x standard.

Safety and environmental data: Class III safety (EN 60730-1), V-0 flame resistance (UL94), and RoHS compliance. Weight: 0.19 kg (with mounting support).