WIKA DW 不銹鋼 差壓開關(guān) 較高觸點(diǎn)負(fù)載能力

高靜壓160bar IP65

                           Differential pressure switch
Stainless steel version, IP 65
Model DW

Differential pressure switch model DW

      Applications
      ■ Differential pressure monitoring and direct switching of electrical loads
      ■ For gaseous and liquid, aggressive and highly viscous or contaminated media, also in aggressive ambience
      ■ Process industry: chemical/petro-chemical, on- and offshore, technical gases, environmental technology,machine building and general plant construction, water treatment, pharmaceutical industry
      ■ Pump monitoring and control / filter monitoring, level measurement in closed tanks

     Special features
     ■ Case made of stainless steel
     ■ Ingress protection IP 65, NEMA 4
     ■ Ambient temperature -30 ... +85 °C
     ■ 1 or 2 independent switch points, high contact rating up to 15 A / AC 220 V
     ■ Working pressure （static pressure） up to 160 bar

    Description
     These high-quality differential pressure switches have been developed especially for safety-critical applications. High quality and product manufacturing to ISO 9001:2000 ensures reliable monitoring of your plant. In production, the switches are traced by quality assurance software at every step and subsequently are 100 % tested.
     All wetted parts materials are from stainless steel or Inconel 718, depending on the measuring range. Each switch family is available in IP 65, Ex-ia or Ex-d versions （Ex-d see model DA, data sheet PV 35.43）.

     In order to ensure as flexible operation as possible, the pressure switches are equipped with micro switches, which make it possible to switch an electrical load of up to 15 A /AC 220 V directly. For smaller contact ratings, such as for PLC applications, argon gas filled micro switches with gold-plated contacts can be selected as an option.
     By using a liquid-filled diaphragm measuring cell with fulcrum lever transmission, the model DW pressure switch is extremely robust and guarantees optimal operating characteristics.

    


     Switch points
     The switch points can be set to your requirements, free-ofcharge.
     Please specify:
     Switch point, switching direction for each contact （e.g. switch point 1: 0.5 bar, falling, switch point 2: 3 bar, rising）
     With two micro switches, the switch points can be set independently of each other.

     After unscrewing the case cover, switch point adjustment can be made using the adjustment screw. The switch point is settable within the entire measuring range with the following
    general rule:
     ■ Define the value A = 2x repeatability + switch hysteresis
     ■ If the pressure is rising, the switch point should be set between （min. + value A） up to max. of the setting range.
     ■ If the pressure is falling, the switch point should be set between min. up to （max. - value A） of the setting range.

    Example:
     Setting range: 0 ... 1 bar with one switch contact Repeatability: 1 % of 1 bar = 10 mbar
    Switch hysteresis = 15 mbar （see table setting ranges） Value A = 2 x 10 mbar + 15 mbar = 35 mbar
    If the pressure is rising, the switch point should be set between 35 mbar up to 1 bar.
    If the pressure is falling, the switch point should be set between 0 up to 965 mbar.
    For optimal performance we suggest the switch point lies between 25 % and 75 % of the setting range.

   Electrical connection
    ½ NPT female, cable connection using internal terminal block, protective conductor connection using internal and external screw, max. earth cable cross-section 4 mm2

  Pressure switch certified per:
   ■ Pressure equipment directive 97/23/EC （PED, annex 1,category IV, safety accessories, module B + D）
   ■ Low voltage directive 73/23 EEC and 93/68 EEC

   Dielectric strength
   Safety class I （EN 61298-2: 1997-06）

   Mounting
   Direct or wall mounting
   Preferred connection location of the process connection should be below.

  Weight
   approx. 6.2 kg

  Options
   ■ Other process connection, also with adapter
   ■ Electrical connection 3/4 NPT, G 1/2, G 3/4 or M20 x 1.5（female）
   ■ Cable gland on request
   ■ Plus/minus setting ranges （e.g. -200 ... +200 mbar）
   ■ 2" pipe-mounting kit （with clamping element）
   ■ Version for off-shore 3） or tropicalised application 3）
   ■ Version for applications to NACE 3）
   ■ Version for ammonia applications 3）
   ■ Oil and grease free version for oxygen applications
   ■ Wetted parts made of Monel
   ■ Design per
   GAS Ex-ia IIC T6 and T4
   Dust Ex-iaD A20 IP65 T85 and T135 3）
  Electrical characteristics: Ui = 30 V
                                  Ii = 100 mA
                                  Pi = 0.75 W
                                  Ci = 0 μF
                                  Li = 0 mH

   ■Accessories:
   Three-way or five-way valve