Type 708 Pressure Regulator Application pressure regulator used to provide pneumatic measuring and control equipment with a constant air supply Set point range 0.5 to bar (8 to 90 psi) The pressure regulator reduces and controls the maximum pressure of bar (80 psi) in a compressed air network to the pressure adjusted at the set point adjuster. Adapter plates allow the supply pressure regulator to be attached directly to pneumatic and electropneumatic devices. The regulator has a filter (0 µm) equipped with a venting plug. Special features Air blow off and low air consumption Almost independent of upstream pressure Any mounting position (except version with filter receptacle) Suitable for pipe and panel mounting as well as for attachment to various positioners and actuators Optionally with pressure gauge Threaded ends G ¼ according to DIN ISO 8/ or with ¼ NPT tapered pipe thread Versions pressure regulator with continuously adjustable set point range of 0.5 to bar (8 to 90 psi). Types 708-0, -, - and -7 (* see table below) are also available with a set point range of 0. to. bar ( to psi). The regulators can be attached to Type 7 Actuators or mounted on rails according to EN 500/05. Standard supply pressure regulator Type 708- x x x x Filter on aluminum basis without filter receptacle* 0 With plastic filter receptacle* With aluminum filter receptacle Stainless steel supply pressure regulator Filter on stainless steel basis w. st. steel receptacle With plastic filter receptacle* Without filter receptacle* 7 Connection G¼ ¼-8 NPT 5 Set point range 0.5 to bar (8 to 90 psi) Without pressure gauge 0 With pressure gauge, completely free of copper With pressure gauge, copper-free housing Fig. Types 708-0, - and - Pressure Regulators Set point range 0. to. bar ( to psi) * Without pressure gauge With pressure gauge, completely free of copper With pressure gauge, copper-free housing 5 pressure regulator with adapter plate for positioners Type 70, 7, 77, 780, 785, 787 ) 5 Type 70, 7, 77, 780, 785, 787 ) 5 Type 7/75 5 5 0 Type 70 5 7 Type 7 5 8 pressure regulator with adapter plate for pn. actuators Type 77 (0 to 700 cm ) with positioner Type 70, 7, 77, 780, 785 or 787 ) 0 Type 7 Filter without pressure gauge Type 708- x x x 0 Aluminum housing and plastic filter receptacle 8 0 Aluminum housing and aluminum filter receptacle 8 0 Stainless steel housing and plastic filter receptacle 8 0 Stainless steel housing and st. steel filter receptacle 8 7 0 ) Selection according to summary on page Associated Information Sheet T 850 EN Edition December 00 Data Sheet T 85 EN
Principle of operation (Figs. and ) The Type 708 Pressure Regulator operates according to the force-balance principle. By turning the set point screw (7), the tension of the spring () is changed and the output pressure is adjusted accordingly. The set point ranges from 0. to. bar or from 0.5 to bar are obtained by using two different springs. The supply pressure regulator contains a filter cartridge () with a mesh size of 0 µm. To drain the condensate open the screw plug () by half a turn. When mounting the regulator, make sure the screw plug is in horizontal or vertical position. For versions with filter receptacle, the regulator must be installed with the receptacle vertically suspended. pressure regulator combined with pneumatic or electropneumatic devices (Figs. to 5, 7, 8) Various adapter plates allow the supply pressure regulator to be attached to the respective devices. Note! If the regulator is connected to supply networks carrying air that contains dust, oil or condensate, it is recommended to use SAMSOMATIC service units for compressed air treatment. 7 8 5..... Installation To avoid the formation of excessive condensate, make sure the supply pressure regulator is installed as closely as possible to the compressor or the compressed air tank. The regulator is either mounted directly into the pipeline or into the appropriate panel cut-out. In addition, it may be attached directly to the positioner or the pneumatic actuator. Depending on the version used, the air connections either provide G ¼ or ¼-8 NPT threads. Fig. Sectional view of Type 708 Pressure Regulator 0 Refer to the Mounting and Operating Instructions EB 85 EN. 0 0 Fig. View of diverting gasket (0) and adjustment knob (0) Legends for Figs. and Body. Seat. Plug. Connecting bore Diaphragm plate. Diaphragm Cover. Venting bore Centering bushing 5 Cap Spring 7 Set point screw 8 Lock mit 0 Diverting gasket Filter cartridge Screw plug 0 Fixing screw Spring washer 0 Adjustment knob T 85 EN
Summary of SAMSON positioners and actuators with associated Type 708-xx Pressure Regulator Positioner For actuator Associated supply pressure regulator Type 7 up to 700 cm Type 77 0 cm and 0 to 700 cm with hooked-up accessories (solenoid valve, lock-up valve) Fig. Type 708-5xx Type 70 Type 7 Type 77 Type 780 Type 785 Type 787 Type 7 00 and 800 cm or single-acting rotary actuators Fig. 5 Type 708-5xx Type 77 0 to 700 cm without any hooked-up accessories Fig. Type 708-xx Type 70 Type 77 0 to 50 cm Fig. 7 Type 708-57xx Type 7 Pneumatic rotary actuators Fig. 8 Type 708-58xx Type 7 Type 75 Type 7 Fig. 9 Type 708-55xx Integral attached version Type 7 for Series V00valves Fig. 0 Type 708-xx T 85 EN
Universal supply pressure regulators and filters Type pressure regulators for universal attachment with piping Fig. Type 708-xxx Photos: -0, -, - Filter with filter receptacle for universal attachment with piping Fig. Type 708-8xxx Photos: -8, -87 Air intake Air discharge with 7 bar supply air Setting range Setting range Set point 0... bar 0... bar 0... bar [bar] P P [bar] 0... bar 5 5.. V n V n 0 0 [m /h] 0 0 5 7 8 9 0 [m /h] Fig. Air flow characteristics of the standard version Table Technical data pressure regulator Typ 708-xx pressure bar (5 psi) above the adjusted set point, however, at least. bar ( psi) Max. bar (80 psi) Set point range 0. to. bar ( to psi) or 0.5 to bar (8 to 90 psi) Air consumption 0.05 m n /h (with 7 bar supply air) Air discharge/intake See diagrams in Fig. Perm. ambient temperature 0 to 70 C Special version down to 5 C Input pressure dependance < 0.0 bar/ p = bar Reversing error 0. bar to 0. bar (depending on the set point) Hysteresis < 0. bar Filter cartridge mesh size 0 µm Pressure gauge Indication range 0 to. bar (0 to psi) or 0 to bar (0 to 90 psi) Connection G 8 Weight 708-0 - - - - -7-5 -5-55 -57-58 - - -8-8 -8-87 Approx. kg 0.8 0.58 0..5..0 0.8 0.95 0.7 0.7 0. 0. 0.87 0. 0. 0.59 0.95 T 85 EN
0 0 G Table Materials Body Polyamide, glass fiber reinforced or stainless steel (.0) for Types 708-/-/-7 Adapter plate Aluminum alloy, anodized black (.7) Stopper and gasket Polyamide, glass fiber reinforced and NBR Cover Polyamide, glass fiber reinforced Cap Polyamide, glass fiber reinforced Plug Polyamide, glass fiber reinforced and polyoxymethylene Plug sealing NBR and VMQ Diaphragm NBR Diaphragm plate Polyamide, glass fiber reinforced Filte receptacle UV-resistant polyamide (Trogamid T 500) Filter cartridge Polypropylene Pressure gauge Housing Stainless steel Connection Stainless steel (version free of copper) Brass, nickel-plated Dimensions in mm Values in parentheses apply to additional compressed air connection as shown in Fig. 5 80 5 (89) Fig. (Photo: Fig. ) Type 708-5xx Pressure Regulator attached to Types 70, 7, 77, 780, 785 and 787 Positioners 70 5 9 Output 9 Fig. 5 (Photo: Fig. 5) Type 708-5xx Pressure Regulator attached to Type 70, 7, 77, 780, 785 or 787 Positioner 9 09 7 9 Fig. (Photo: Fig. 9) Type 708-55xx Pressure Regulator attached to Type 7 or Type 75 Positioner 0 708-55. 5 Output 55 (90) 5 T 85 EN
5 0 S Input 7 G Output Output 8 8 G/8 5 9 Input signal Fig. 7 (Photo: Fig. 7) Type 708-57xx Pressure Regulator attached to Type 70 Positioner 7 0 7 99 (57) 09 Fig. 8 (Photo: Fig. 8) Type 708-58xx Pressure Regulator attached to Type 7 Positioner 9 0 (8) 09 0 5 80 88 Fig. 9 (Photo: Fig. ) Type 708-xx Pressure Regulator for Type 77 Pneumatic Actuator T 85 EN
0 708-X G 9 (5) 9 57 SAMSON 99 5 99 5 Fig. 0 (Photo: Fig.) Type 708-xx/-xx Pressure Regulator 90 () 9 50 50 78 Fig. (Photo: Fig. ) Type 708-xx/xx Pressure Regulator Fig. (Photo: Fig. 0) Type 708-xx Pressure Regulator for Type 7 Pneumatic Actuator 7 T 85 EN
50 9 78 (0) 0 G 708-. -... 50 78 Ordering text pressure regulator Without filter receptacle Compact version with filter receptacle made of plastic Monoblock version with filter receptacle made of aluminum or stainless steel For positioners Type 70, 7/7, 780, 785, 787 Type 7/5 or Type 70 or Type 7 For pneumatic actuators Type 77 (0, 0, 50, 700 cm ) or Type 7 (0, 80, 0, 0, 50, 700, 00 and 800 cm ) Type 7 (0 cm ) Type... Rotary Actuator Fig. (Photo: Fig. ) Type 708-0xx/-7xx Pressure Regulator 59 Universal filter Filter receptacle Pressure gauge Connection Plastic, aluminum or stainless steel Brass, nickel-plated, housing free of copper or Stainless steel version (completely free of copper) 5 9 Threaded connection G ¼ or ¼-8 NPT Accessories Mounting parts For valve attachment or DIN rails acc. to EN 500 or DIN rails acc. to EN 5005 Intermediate plate for additional compressed air connection Fig. (Photo: Fig. ) Type 708-8xx/-8xx/-8xx/-87xx Compressed Air Filter Special versions Cryogenic version suitable for temperatures down to 5 C Silicone-free version suitable for temperatures ranging between 0 C and 70 C 90 Fig. 5 Intermediate plate for additional air connection Example showing Type 708-55xx Specifications subject to change without notice. SAMSON AG MESS- UND REGELTECHNIK Weismüllerstraße 0 Frankfurt am Main Germany Phone: +9 9 009-0 Fax: +9 9 009-507 Internet: http://www.samson.de T 85 EN