Symaro™ Room sensors for relative humidity and temperature Modbus RTU QFA2050/MO, QFA2050D/MO Room relative humidity and temperature sensors with Modbus communication ● ● ● A6V12046135_en--_a 2020-07-23 Modbus RTU (RS-485) Relative humidity measuring accuracy of 3 % within the comfort range DIP switches set together with other controllers Smart Infrastructure
Use QFA2050/MO and QFA2050D/MO are used in ventilation and air conditioning plants to acquire room ● relative humidity ● temperature The sensor is used as a measuring sensor for building automation and control systems or display units. Technical design The units are designed for wall mounting and can be deployed with most types of commercially available recessed conduit boxes. The cables can be introduced from the rear (concealed wiring), from below or above (surface-run wires) through knock-out openings.
Cable routing and cable selection Note that when routing cables, the longer the cable runs and the closer the cables, the greater the electrical interference. Use shielded cables in EMC-prone environments. Twisted pair cables are required for both secondary supply lines and signal lines. Mounting Location Inner wall (not exterior!) in the room to be air conditioned; not in niches, not behind curtains, not above or close to heat sources or shelves nor on walls with a chimney.
Technical data Function Communication Modbus RTU (RS-485) Supported baud rate 9600; 19200; 38400; 57600; 76800; 115200 Transmission format 1-8-E-1; 1-8-O-1; 1-8-N-1; 1-8-N-2 Bus termination 120 ohm, jumper selection For detailed information on specific functions, see Basic documentation (A6V12045847 *). Power supply Operating voltage AC 24 V ±20 % or DC 13.5…35 V (SELV) or AC/DC 24 V class 2 (US) Frequency 48...63 Hz at AC 24 V External supply line protection Fuse slow max.
Ambient conditions and protection classification ● Mechanical conditions Class 2M2 Operation IEC 60721-3-3 ● Climatic conditions Class 3K5 – -15...50 °C ● Temperature (housing with electronics) – Humidity Mechanical conditions < 95 % r.h.
Diagrams Connection terminals 6 Siemens Smart Infrastructure G Operating voltage AC 24 V ±20 % or DC 13.5...
Dimensions Dimensions in mm Siemens Smart Infrastructure Datasheet 7 A6V12046135_en--_a 2020-07-23
Issued by Siemens Switzerland Ltd Smart Infrastructure Global Headquarters Theilerstrasse 1a CH-6300 Zug Tel. +41 58 724 2424 www.siemens.com/buildingtechnologies 8 Siemens Smart Infrastructure Document ID A6V12046135_en--_a Edition 2020-07-23 © Siemens Switzerland Ltd, 2020 Technical specifications and availability subject to change without notice.
