Technical Documentation Flow rate controllers type VRE-W (short) LTG Aktiengesellschaft 70435 Stuttgart, Grenzstraße 7, Germany Tel. +49 711 8201-0, Fax +49 711 8201-720 [email protected] www.LTG-AG.com LTG Incorporated 105 Corporate Drive, Suite E Spartanburg S.C. 29303, USA Tel. +1 864 599-6340, Fax +1 864 599-6344 [email protected] www.LTG-INC.net LTG S.r.l. con socio unico Via Matilde Serao 5, 20144 Milano (MI), Italy Tel. +39 02 9550535, Fax +39 02 9550828 [email protected] www.LTG-SRL.com

Flow rate controllers type VRE-W (short) Air-Water Systems Content Page Views of unit, application, measuring principle, 3 Materials, finishes, accessories, special 4 versions, connection, selection, application ranges, flow rates Control accuracy, installation conditions 5 Airborne sound transmission 7 Casing radiation without insulating case 8 Casing radiation with insulating case 9 Specification and schedule of prices Dimensions stated in this brochure are in mm. Dimensions stated in this brochure are subject to General The actual specifications are at the end of this document. They are available...

Flow rate controllers type VRE-W (short) Views of unit Measuring principle Contrary to conventional measuring techniques, the differential pressure is not measured through a series-connected element such as an orifice plate. Instead, differential pressure measured by two cup-shaped elements mounted in the damper blade area. Placing the damper blade in the throttle position creates a „jet effect”, which is concentrated with reduced flow rates and higher throttle settings. This results in increased air speeds at the measuring point even with lower duct air speeds allowing for relatively high and...

Flow rate controllers type VRE-W (short) Materials, finishes Application ranges and limits - Housing, damper, axle and and measuring probes of galvanized steel - Damper bearings of POM plastic - Sealings of EPDM - Minimum air speed 1 m/s - Nominal air speed 10 m/s - Maximum air speed in the free case section 12 m/s with specific factory-set adjustment - Static over-pressure in the air duct up to 1000 Pa - Static under-pressure in the air duct based on ambient pressure 750 Pa max. - Leakage flow rate via shut damper blade Class 3, DIN EN 1751 - Leakage flow rate via casing Class A, DIN EN 1751...

Flow rate controllers type VRE-W (short) Control accuracy, installation conditions Control accuracy Deviations from the set value: ± 5% at Vnenn (equates to 10 m/s) up to ± 15% at Vmin (equates to 1 m/s). Required straight inflow distances A straight, undisturbed inflow distance of approx. 0.5 ... 3 x D (mm) in front of the flow rate controller is required. There are, however, no restrictions regarding the outflow side. Please ensure a perfect positioning of the measuring nipples with respect to the air flow. Avoid turbulent air flow and short radius bends or T-branches before the damper. Min...

Flow rate controllers type VRE-W (short) Dimensions, weights L1 Version with plug-in ends and lip seal gasket, without insulating case. Total length of the housing of the version with flange L + 2 x L1. Version with plug-in ends and lip seal gasket, with insulating case. Total length of the housing of the version with flange L + 2 x L1. Nominal diam. DN Damper angle [_] insulating case E LTG Aktiengesellschaft Grenzstraße 7 70435 Stuttgart Germany Tel. +49 711 8201-0 Fax +49 711 8201-720 [email protected] www.LTG-AG.com Printed in Germany · Former editions are invalid · Subject to technical modifications...

Flow rate controllers type VRE-W (short) Airborne sound transmission ∆pges = 100 Pa Nominal size Total pressure difference Octave mid-band frequency Sound power level Sound power level, A-weighted Sound pressure level, A-weighted E LTG Aktiengesellschaft Grenzstraße 7 70435 Stuttgart Germany Tel. +49 711 8201-0 Fax +49 711 8201-720 [email protected] www.LTG-AG.com Printed in Germany · Former editions are invalid · Subject to technical modifications

Flow rate controllers type VRE-W (short) Casing sound emission without insulating case ∆pges = 200 Pa Sum Nominal size Casing sound emission data given in the chart refer to the emitting jacket surface of a duct of galvanized sheet steel, total length 6 m, with the flow rate controller installed. Due to resonance effects given frequency-related sound power level data may vary by +/- 6 dB max. Legend ∆pges fm LW LWA LpA - Total pressure difference Octave mid-band frequency Sound power level Sound power level, A-weighted Sound pressure level, A-weighted E LTG Aktiengesellschaft Grenzstraße 7 70435...

Flow rate controllers type VRE-W (short) Casing sound emission with 50 mm insulating case ∆pges = 100 Pa Nominal size Casing sound emission data given in the chart refer to the emitting jacket surface of a duct of galvanized sheet steel, total length 6 m, with the flow rate controller installed. Both the flow rate controller and the duct are provided with a 50 mm insulating case. Due to resonance effects given frequency-related sound power level data may vary by +/- 6 dB max. Legend ∆pges fm LW LWA LpA - Total pressure difference Octave mid-band frequency Sound power level Sound power level,...

Flow rate controllers type VRE-W (short) Room sound pressure level calculation from controller sound transmission (excluding flow noise from the air diffusers) System attenuation according to VDI 2081 fm Branching attenuation for distributing the sound power over multiple rooms, Vroom = 540 m³/h [m³/h] Sample calculation sound transmission Given: VRE-W 125 without silencer Vmax = 172 m³/h, equates to 4 m/s ∆pges = 200 Pa Required: Room sound pressure level LpA from controller sound transmission Solution: fm Sound power level Room attenuation Outlet reflection A-weighted sound pressure level LpA...

Flow rate controllers type VRE-W (short) Nomenclature, ordering key VRE-W ... / . / . / . / .. ... (1) (2) (3) (4) (5) (6) (1) Flow rate controller, round, short (2) Size or diameter L = plug-in end pieces with lip seal gasket F = flanges acc. to DIN 24154 R1 BI 671 = Belimo LMV-D3W-MF-F (standard) Bl 670 = Belimo LMV-D3W-MP-F (special version) Bl 802 = Belimo LMV-D3W-LON-F (special version) Additional ordering specifications - Vmin [m³/h], at which 0 ≤ Vmin ˂ Vmax; lower limit of control see page 4 - Vmax [m³/h], at which Vmin ˂ Vmax ≤ Vnenn and Vmax ≥ 0,2 Vnenn; Vnenn see page 4 - Mode: 0 ......