Elektro Kalori Ürün Kataloğu

www.elektrokalori.com.tr BİNA OTOMASYON ÜRÜNLERİ 257 Size and select combi valves 1 Determine Q 100 Q 100 2 Determine ∆ T ∆ T 3 Calculate V Water without anti-freeze Q 100 1.163·∆T V 100 = Water with anti-freeze Q 100 · 3600 c· ρ ·∆T V 100 = Select combi valve and actuator 4 Select suitable combi valve a) Type of valve (with / without P/T plugs) b) PN class e) Nominal size DN c) Max. / min. medium temperature f) Medium 5 Determine presetting / dial table in data sheet of the respective combi valve 6 Select actuator a) Operating voltage b) Positioning signal c) Positioning time d) Auxiliary functions 7 Check working range a) ∆ p < ∆ p max – maximum permissible differential pressure across the valve’s control path, valid for the entire actuating range of the motorized valve b) ∆ p > ∆ p min – inim mum differential pressure required across the valve’s control path, so that the differential pressure regulator works reliably 8 Select actuator Combi valve and suitable actuator Selection of valve and actuator 7 Select suitable valve series a) Type of valve (2-port, 3-port, 3-port with bypass) c) PN class d) Nominal size DN e) Max. / min. medium temperature f) Medium 8 Check valve authority P v (control stability) ∆p V100 ∆p VR P V = ≥ 0.25…0.8 ∆p V100 ∆p V100 + ∆p MV P V = ≥ 0.25…0.8 9 Select actuator a) Operating voltage b) Positioning signal c) Positioning time d) Spring return function e) Auxiliary functions 10 Check working range a) Differential pressure ∆ p max > ∆ p V0 b) Closing pressure ∆ p s > H 0 11 Selection Valve and suitable actuator Abbr. Term Unit ∆ p Differential pressure kPa Pressure differential between plant sections. ∆ p max Maximum differential pressure kPa Maximum permissible differential pressure across the valve’s control path (when mixing), valid for the entire actuating range of the motorized valve. ∆ p maxV Maximum differential pressure kPa Maximum permissible differential pressure across the valve’s control path (when distributing), valid for the entire actuating range of the motorized valve. ∆ p min Minimum differential pressure kPa Minimum differential pressure required, so that the differential pressure regulator works reliably with combi valves. ∆ p min depends on presetting position, see data sheet for details. ∆ p V0 kPa Maximum differential pressure across the valve’s closed control path. ∆ p V100 Differential pressure at kPa 100 . ∆ p s Closing pressure kPa For 2-port valves, maximum permissible differential pressure at which the motorized valve will close securely against the pressure (close off pressure). Only valid for 2-port valves. ∆ p MV kPa MV is not known, in which case typical values can be used. ∆ p VR kPa ∆ T Temperature spread K DN Nominal size Characteristic for matching parts of the piping system. H 0 Shutoff head m The head generated by a pump at closed value, at a given speed and a given pump medium. kPa Unit of pressure kPa 100 kPa = 1 bar = 10 mWC mWS Meter water column m k V m³/h Amount of cold water (5…30 °C) passing through the valve at the respective stroke and at a differential pressure of 100 kPa (1 bar). k VS m³/h en valve (H100) at a differential pressure of 100 kPa (1 bar). Spring return function Shutoff in the event of a power failure. PN PN class Characteristic relating to the combination of mechanical and dimensional properties of a compo- nent in the piping system. Phs Phase cut control signal V DC 0...20 V Phs P v Valve authority Ratio of differential pressure across fully open valve (H100) and differential pressure across valve ve authority of 0.25 is required. Q 100 Rated capacity kW Plant’s design capacity. V 100 m³/h (H 100 ). V min m³/h i valve (H 100 ). ν Kinematic viscosity mm²/s In the case of kinematic viscosities ν up to 10 mm²/s, no corrections are required. For the selection of actuating devices for kinematic viscosities ν above 10 mm²/s, c kJ/kgK ρ kg/m³ Acvatix Valves and Actuators