VAV Controllers LVC-LowVelocity - TROX

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Functional description Volume flow rate measurement A new measurement principle makes it possible to measure low volume flow rates. The pressure is measured by means of a nozzle with tappings upstream and downstream of the damper blade. The Compact controller of the LVC-LowVelocity determines the resulting pressure differential (effective pressure) and compares it to the stored characteristic. This measurement principle is characterised by small measuring tolerances, and the upstream flow conditions do not have to meet any special requirements. Volume flow rate control The volume flow rate is controlled in a closed loop, i.e. measurement – comparison – control. First, measurement takes place. The controller then compares the actual measured value to the setpoint value, which in most applications is received from a room temperature controller. In case of a deviation, the controller sends a signal to the actuator, and the actuator moves the damper blade accordingly. Room temperature control In VAV systems, the room temperature control takes the form of a cascade control. The room temperature is the primary controlled variable. The output signal from the room temperature controller controls the supply air flow rate. Flow rate control also means defining minimum and maximum flow rates, and not only does this help to keep the room temperature constant but has advantages for the entire air conditioning system. Supply/extract air tracking control In individual rooms the balance between supply and extract air should be maintained. Otherwise, annoying whistling noises can occur at door gaps, and the doors can be difficult to open. This is also why the extract air is controlled in a VAV system (tracking control). The actual supply air value is fed to the extract air controller, and the extract air consequently follows the supply air flow rate even when the supply air deviates from the setpoint value. Control principle Control diagram V Nom V max 2 3 1 Setpoint value TROX Compact controller Vmin V min unit 1 Volume flow controller 2 Differential pressure transducer 3 Actuator Control signal for the VAV controller Upstream flow conditions Upstream bend Branch off the main duct 1 D D 4
Construction · Dimensions Characteristics – Electronic flow rate control – Suitable for supply and extract air – High control accuracy, even in case of unfavourable upstream flow conditions – Differential pressure range: 30 to 600 Pa – Shut-off by means of a switch (supplied by customer) – Leakage when the damper blade is closed complies with EN 1751, class 3 – Any installation orientation is possible – Transparent protective cover for general safety and to prevent inadvertent resetting – Wire clamping bracket – Factory setting and aerodynamic function testing of every individual unit on a special test rig Construction features – Both spigot connections with lip seals, suitable for ducts according to EN 1506 or EN 13180 – Casing air leakage complies with EN 1751, class C – Mechanical parts of the VAV controller are maintenance-free Materials – Casing in galvanised sheet steel – Nozzle, damper blade, and plain bearings made of ABS plastic, UL 94, flame retardant (V0) – Damper blade seal made of TPV plastic General Information Standard filtration in comfort conditioning systems is such that the TROX Compact controller can be used in the supply air without additional dust protection. To select volume flow controllers for dust laden or aggressive extract air refer to the Easy Product Finder design programme on our homepage. Dimensions 310 50 50 300 Ø Da 300 20 76 Keep clear to provide access to control components Dimensions in mm Nominal size ØDa 125 124 160 159 200 199 250 249 Weight in kg Nominal size 125 1.5 160 1.9 200 2.1 250 2.7 TROX Compact controller – Technical data Supply voltage Power rating Control signal Flow rate actual value signal IEC protection class Protection level IP 20 24 V AC ± 20 %, 50/60 Hz or 24 V DC −10 % / +20 % 5 VA max. (for AC voltage) 3 W max. (for DC voltage) 0 to 10 V DC, Ri > 100kΩ 0 to 10 V DC linear, 0.5 mA max. III (Safety Extra Low Voltage, SELV) 5
Page 1 and 2: 5/5/EN/1 VARYCONTROL VAV Controller
Page 3: Innovation TROX LVC-LowVelocity - t
Page 7 and 8: Acoustic quick selection Using quic
Page 9 and 10: Case-radiated noise Example (contd.
Page 11 and 12: Flow characteristics · Wiring exam

VAV Controllers LVC-LowVelocity - TROX

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