Title: +038=310.101-SC020T_01-FDV-dokumentasjon - Danfoss AS - VA_VVS 5640741 med flere - EV220B 15-50_1.pdf
Coil voltage disconnected (closed): When the voltage is disconnected, the valve plate (3) is pressed down against the pilot orifice (4) by the armature spring (2). The pressure across the diaphragm (5) is built up via the equalizing orifice (7). The diaphragm closes the main orifice (6) as soon as the pressure across the diaphragm is equivalent to the inlet pressure. The valve will be closed for as long as the voltage to the coil is disconnected.1. Coil 2. Armature spring 3. Valve plate 4. Pilot orifice 5. Diaphragm 6. Main orifice 7. Equalizing orificeCoil voltage connected (open): When voltage is applied to the coil (1), the pilot orifice (4) is opened. As the pilot orifice is larger than the equalizing orifice (7), the pressure across the diaphragm (5) drops and therefore it is lifted clear of the main orifice (6). The valve is now open for unimpeded flow and will be open for as long as the minimum differential pressure across the valve is maintained, and for as long as there is voltage to the coil.