Type LVC

 

Circular VAV terminal units for variable air volume systems with low airflow velocities, suitable for supply or extract air, available in four nominal sizes.

Measurement and control of low volume flow rates based on a new measurement principle. Plastic nozzle with damper blade for measuring the differential pressure upstream and downstream of the damper blade (effective pressure). The relation between damper blade position and differential pressure is stored as a characteristic relationship in the Easy or Compact controller. This results in high control accuracy even in case of unfavourable upstream conditions.

Selection based on nominal size determination.

Ready-to-commission unit which consists of the mechanical parts and the electronic control components. Units are equipped with a plastic nozzle with integral damper blade.

The averaging differential pressure sensor is resistant to dust and pollution.

Spigot with lip seal, for circular connecting ducts to EN 1506 or EN 13180.

Position of the damper blade indicated externally at shaft extension. Damper blade is factory set to open position which allows ventilation airflow even without control.

Closed blade air leakage to EN 1751, at least class 1.

Casing air leakage to EN 1751, class C.

Special features

• Optimised for low airflow velocities from 0.6 to 6 m/s
• High control accuracy even in case of unfavourable upstream conditions
• Any installation orientation
• Volume flow rate control with Easy or Compact controller
• Casing length of only 310 mm

Materials and surfaces

• Casing made of galvanised sheet steel
• Nozzle, damper blade, and plain bearings made of ABS plastic, UL 94, flame retardant (V-0)
• Damper blade seal made of TPV (plastic)

Technical data

• Nominal sizes: 125 – 250 mm
• Volume flow rate range:  8 – 300 l/s or 30 – 1080 m³/h
• Volume flow rate control range: approx. 10 – 100 % of the nominal volume flow rate
• Running time for 90°: 90°: 110 – 150 s
• Minimum differential pressure: 5 – 30 Pa
• Maximum differential pressure: 600 Pa

Attachments

Variable volume flow control with electronic Easy controller to connect an external control signal; actual value signal can be integrated into the central BMS.

• Supply voltage 24 V AC/DC
• Signal voltages 0 – 10 V DC
• Possible override controls with external switches using volt-free contacts: CLOSED, OPEN, V_min and V_max
• Potentiometers with percentage scales to set the volume flow rates V_min and V_max
• The actual value signal relates to the nominal volume flow rate such that commissioning and subsequent adjustment are simplified
• Volume flow rate approx. 10 – 100 % of the nominal volume flow rate
• Clearly visible external indicator light for signalling the functions: Set, not set, and power failure

Electrical connections with screw terminals. Double terminals for looping the supply voltage, i.e. for the simple connection of voltage transmission to the next controller.