DWR Pressure monitors DWR625 tested DVGW TÜV Product Summary Steam Systems according to TRBS Hot water Systems according to DIN EN12828 Fuel gases DVGW work sheet G 260 Pressure tank DIN EN764-7 Pressure monitor or pressure limiter (with external interlock) For maximum and minimum pressure monitoring (DWFS, SDBFS) "of special construction" by testing with 2 million cycles. Component tested for Function Direction of action Sensor -DWR see page 66 Technical data Pressure connection External thread G 1/2 (pressure gauge connection) to DIN 16 288 and internal thread G 1/4 to ISO 228 Part 1 (for gas applications internal thread permissible only up to 4 bar). Switching device Rugged housing (200) made of seawater resistant die cast aluminium. Materials Pressure bellows: Material no. 1.4571 Sensor housing: Material no. 1.4104 Switch housing: GD AI Si 12 (DIN 1725) Mounting position Vertically upright and horizontal. Ambient temperature at switching device –25 to +70°C, Medium temperature –25 to +70°C. The maximum medium temperature at the pressure sensor must not exceed the permitted ambient temperature at the switching device. Temperatures may reach 85°C for short periods. Higher medium temperatures are possible provided the above limit values for the switching device are ensured by suitable measures (e.g. siphon). Mounting Directly on the pressure line (pressure gauge connection) or on a flat surface with two 4 mm Ø screws. Calibration The DWR series is calibrated for rising pressure. This means that the adjustable switching pressure on the scale corresponds to the switching point at rising pressure. The reset point is lower by the amount of the switching differential. (See also page 23, 2. Calibration at upper switching point). In version ...-203 the switching differential is adjustable. The basic calibration is maintained. Bursting pressure For all types ≥ 100 bar, verified by TÜV test. Switching differential For values see Product Summary. Contact arrangement Single pole change over switch. Protection class IP 54 according to DIN 40 050 Switching 250 VAC 250 VDC 24 VDC capacity (ohm) (ind) (ohm) (ohm) Normal 8 A 5 A 0.3 A 8 A SIL 2 according IEC 61508-2 Type Setting range Switching differential (Tolerance) Maximum working pressure Dimensioned drawing Pressure monitors without differential adjustment p. 21 + 22 DWR06 0,1…0,6 bar 10 ... 50 mbar 6 bar 1 + 15 DWR1 0,2…1,6 bar 40 ... 100 mbar DWR3 0,2…2,5 bar 40 ... 160 mbar 16 bar 1 + 18 DWR6 0,5…6 bar 0,08 ... 0,3 bar DWR625 0,5…6 bar 0,08 ... 0,3 bar 25 bar 1 + 17 DWR16 3…16 bar 0,2 ... 0,6 bar DWR25 4…25 bar 0,3 ... 1,5 bar 63 bar 1 + 16 DWR40 8…40 bar 0,8 ... 1,6 bar Switching differential adjustable DWR06–203 0,1…0,6 bar 0,08 … 0,5 bar 6 bar 1 + 15 DWR1–203 0,2…1,6 bar 0,15 … 0,6 bar DWR3–203 0,2…2,5 bar 0,17 … 1,4 bar 16 bar 1 + 18 DWR6–203 0,5…6 bar 0,3 … 1,7 bar DWR625–203 0,5…6 bar 0,4 … 2,5 bar 25 bar 1 + 17 DWR16–203 3…16 bar 0,75 … 3,15 bar DWR25–203 4…25 bar 1,3 … 6,0 bar 63 bar 1 + 16 DWR40–203 8…40 bar 2,3 … 6,6 bar phone: (86)021-37785053 Mobile:17821719638 www.femachina.com.cn 15 Accessories Pressure switches Pressure transmitters Thermostats Temperature sensors Flow monitors Solenoid valves 15 Mechanical pressure switches Technical features / Advantages Mechanical pressure switches Technical features / Advantages Wall mounting or directly on the pressure line Switching element (microswitch) Lead sealable setpoint adjustment Setting spindle locking element Terminal connection or plug connection to DIN EN175301 Form A Stainless steel sensor housing Stainless steel bellows with internal stop Pressure connection G 1/2" external G 1/4" internal Centring pin Diecast aluminium housing IP 54 or IP 65 version also available phone: (86)021-37785053 Mobile:17821719638 www.femachina.com.cn 16 Mechanical pressure switches Definitions Definitions Pressure data Overpressure Pressure over the relevant atmospheric pressure. The reference point is atmospheric pressure. Vacuum Pressure under the relevant atmospheric pressure. The reference point is atmospheric pressure. Absolute pressure Overpressure relative to absolute vacuum. Differential pressure Difference in pressure between 2 pressure measuring points. Relative pressure Overpressure or vacuum relative to atmospheric pressure. Pressure data in all FEMA documents refers to relative pressure. That is to say, it concerns pressure differentials relative to atmospheric pressure. Overpressures have a positive sign, vacuums a negative sign. Permissible working pressure (maximum permissible pressure) The maximum working pressure is defined as the upper limit at which the operation, switching reliability and water tightness are in no way impaired (for values see Product summary). Bursting pressure (test pressure) Type-tested products undergo a pressure test certified by TÜV affirming that the bursting pressure reaches at least the values mentioned in the Product summary. During the pressure tests the measuring bellows are permanently deformed, but the pressurized parts do not leak or burst. The bursting pressure is usually a multiple of the permissible working pressure. Setting range Pressure range in which the cutoff pressure can be set with the setting spindle. Pressure units Important: All pressure data refers to overpressures or vacuums relative to atmospheric pressure. Overpressures have a positive sign, vacuums a negative sign. In FEMA documents pressures are stated in bar or mbar. Pressure data for a pressure switchbased on the example of DWR625: Setting range: 0.5-6 bar Perm. working pressure: 20 bar Bursting pressure: >100 bar Unit bar mbar Pa kPa MPa (psi) Ib/m² 1 bar 1 1000 10⁵ 100 0.1 14.5 1 mbar 0.001 1 100 0.1 10-4 0.0145 1 Pa 10-5 0.01 1 0.001 10-6 1.45 · 10-4 1 kPa 0,01 10 1000 1 0.001 0,145 1 MPa 10 104 106 1000 1