User Manual

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Sensor selection
Here are some rules to help with sensor selection:
1. An ideal choice for IAQ is one of Siemens’ combined CO
2 and VOC sensors (AQR.., QPA..
or QPR..). The sensor element measuring the higher demand (be it CO
2 or VOC) will
determine the flow rate of fresh air.
2. Room or air duct sensors? In principle, IAQ can be measured either in the room itself or
in the extract air duct. Room sensors enable the plant to be switched off completely,
thus maximizing energy savings. They can also be positioned to detect the main sources
of pollution directly.
3. Number of sensors: for spaces of up to 400 m
2
with a simple geometry, one sensor
is usually enough.
8.5 VAV controllers
Siemens offers two approaches to VAV controllers: the first option is a separate room
controller and a VAV compact controller (see table below for the VAV compact controllers
GDB.. and GLB..). The second option is a room controller and VAV compact controller
combined in one single hardware product (see the tables below, showing DXR1.. and DXR2..).
VAV compact controller GDB181.1E/KN
(KNX)
GLB181.1E/KN
(KNX)
GDB181.1E/3
DC 0…10 V or
DC 2…10 V
GLB181.1E/3
DC 0…10 V or
DC 2…10 V
Features
Communication KNX PL-Link
KNX LTE-/S-Mode
KNX PL-Link
KNX LTE-/S-Mode
- -
Torque (Nm) 5 10 5 10
Air damper area (m
2
) 0.8 1.5 0.8 1.5
Operating range (Pa) 0…300 0…300 0…300 0…300
Operating voltage (AC) 24 24 24 24