LEO

Leo is a volume flow controller which works independently of the duct pressure. It is the desired air flow rate at choked damper that determines the duct pressure required for the applicable unit/string. The VAV unit is based on dynamic measurement of volume flows, and controls the damper position to maintain the air flow rate required. When a change in duct pressure occurs, such as when other volume flow controllers on the branch open or close, the unit will compensate by adjusting the damper until the correct volume flow has been restored. The required air flow rate can, for example, be provided as a 0-10V signal from room thermostat / CO² sensor in the occupied zone covered by the unit. Minimum and maximum air flow rates can be set at the factory or during installation by using a service tool from Belimo or Siemens. The VAV unit is designed to provide comfort ventilation at temperature conditions of between 0°C and 50°C and a relative humidity between 5% and 95% without condensation. A 4-conductor cable connects the controller to various control equipment in the room. Consistent use of a common reference system for all equipment is important. For the VAV controller, cable no. 1 is system-0. All control and measurement signals are linked up in accordance with this. Wiring diagram for Leo in combination with various room control equipment is available at our website www.trox.no For energy-efficient operation, VAV systems are equipped with pressure sensors in the ductwork, which transmit control signals to branch dampers or to the fan frequency control. Please see schematic diagram in fig.1.

Leo VAV is a complete measuring and control unit where the air flow rates in ventilation systems can be set as required. At the measuring station, the differential pressure is measured via measuring rod integrated in the unit. The unit is installation-friendly in terms of straight ducting, and can thus be mounted in most ductwork sections. It is fully compliant with air permeability class 4 for damper in closed position, and class C for leakage to the surroundings. Leo is equipped with VAV controller from Belimo or Siemens.

Belimo LMV-D3-FK AU is used from dim. 100 to dim.400. 
Belimo NMV-D3 AU is used from dim. 500 to 630. 
Siemens GDB181.1E is used from dim. 100 to dim.315. 
Siemens GLB181.1E is used from dim. 400 to dim. 630. 
Controller specifications are provided in table 1. Full technical documentation can be downloaded from our website www.trox.no. Belimo LMV/NMV-D3 is used as analog control or for MP-bus. Belimo MOD/BACnet controller or Siemens BACnet controller is also available. For KNX, Belimo LMV-D3-KNX and NMV-D3-KNX or Siemens GDB181.1E/KN and GLB181.1E/KN is available. If additional protection against structure-borne noise is required, e.g. for open installation, the unit can be delivered with external insulation and casing. This will reduce the level of noise emitted from the actual unit at high choke pressure and high velocity past the damper. However, this should be followed up with additional protection against structure-borne noise from the duct at both sides of the unit. Please see acoustic datasection. The LEV sound attenuator is designed for VAV systems, and is available in 500mm and 1000mm lengths. LEV has a full attenuator cross-section, and this ensures a low-level pressure loss. It is insulated with mineral wool featuring a reinforced top layer to prevent fibres breaking away with the supply air. An extraction unit with mesh grille, ASN, in the same design as LEV is also available. Leo-D, LEV and ASN can be delivered pre-assembled with ducting clips and are equipped with adjustable brackets from factory.