Siemens QPA2000 Overview:
In ventilation and air conditioning plants to enhance room comfort and optimize energy consumption by providing demand-controlled ventilation. The sensor acquires CO2 concentrations as an indication of occupancy in rooms where smoking is prohibited.QPA2000 can be used as a control sensor or transmitter for building automation and control systems.
QPA2000's CO2 measuring range is 0-2000 ppm.
Typical use: In rooms with varying occupancy levels where smoking is prohibited such as party rooms, lounges, fair pavilions and exhibition halls, restaurants, canteens, shopping malls, athletic centers, sales rooms, and conference rooms.QPA2000 sensors may not be deployed as safety devices, e.g. as gas or smoke warning devices!
QPA2000 Technical Data:
- Operating voltage: AC 24 V r20 % oder DC15-35 V (SELV) oder AC/DC 24 V class 2 (US)
- Frequency: 50/60 Hz at AC 24 V
- External supply line protection (EU):Fuse slow max. 10 A or Circuit breaker max. 13 A Characteristic B, C, D according to or Power source with current limitation of max. 10 A
- Power consumption: 1.7 VA, typ. 0.5 VA
- Measuring range: 0-2000 ppm
- Measuring accuracy at 23 deg;C and 1013 hPa: less than +/-(50 ppm + 2 % of measured value)
- Temperature dependency in the range of -5…45 deg;C: +/-2 ppm / (typically)
- Long-time drift: less than +/-5% of measuring range / 5 years (typically)
- Recalibration-free: 8 years
- Ambient temperature, operation: 0-50 °C
Connection, electrical:Screw terminals
- Degree of protection: IP30
- Dimensions (W x H x D): 90 x 100 x 36 mm
QPA2000 Mode of Operation:
CO2 concentration: Symaro air quality sensors acquire the CO2 concentration by infrared absorption measurement (NDIR). The resulting output signal DC 0-10 V or DC 0-5 V is proportionate to the CO2 content of ambient air.
QPA2000 Mechanical Design:
QPA2000 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 knockout openings.
The units consist of 2 major sections: Casing and base plate. Both snap together but can be detached again.
The measuring circuit, the sensing elements, and the setting elements are located on a printed circuit board in the unit. The mounting base carries the connection terminals.
QPA2000 Setting Elements:
For the CO2 measuring range: Jumper in the mid position (R2) = 0-2000 ppm (factory setting)
For output voltage:
- Plugged in jumper = DC 0-10 V
- Removed jumper = DC 0-5 V
For the unit of temperature:
- Jumper in the horizontal, lower position = °C (factory setting)
- Jumper in the horizontal, upper position = °F
In the event of fault: In the event of CO2 failure, DC 10 V or 5 V is present at signal output U1 (after 60 seconds).
QPA2000 Connection Terminals:
QPA2000 Mounting Location:
QPA2000 should be mounted on inner wall of the room to be ventilated, not in niches, not behind curtains, not above or near heat sources, and not exposed to direct light from spot lights. Do not expose the sensor to direct solar radiation. Seal the end of the conduit at the sensor to prevent false measurements due to drafts through the conduit.
QPA2000 Mounting Instruction: