INSTALLATION AND SERVICE INSTRUCTIONSiemens Industry, Inc. SD74 Rev. 19 January 2011 Supersedes Issue 18 Model Series 74 Valve Posi
SD74 10 6 PSI INSTR. PRESS. SPAN. 12 PSI INSTR. PRESS. SPAN 15 PSI INSTR. PRESS. SPAN 24 PSI INSTR. PRESS. SPAN 30 PSI INSTR. PRESS. SPAN Stroke “C”
SD74 11TABLE 2-1 Double-Acting Cylinder Operators VALVE DESIGN Valve Action Down to Close Up to Close Down to Close Up to Close Maximum
SD74 122.5 RANGE AND SUPPRESSION SPRING KITS There are three spring kits: rectilinear range, rotary range, and suppression. Each is packaged separat
SD74 13 ITEM DESCRIPTION 1 Model 74 2 Enclosure Assembly 3 Spring Assembly (includes: range spring, traveling washer, span adjusting screw, and l
SD74 144. Place range spring assembly on actuator shaft. 5. Attach the range spring link to the input diaphragm assembly stem (See Figure 4-1). 6.
SD74 153.0 CALIBRATION 3.1 VALVE POSITIONER The Model 74, when used as a valve positioner, has three calibration adjustments: Zero, span and outp
SD74 16 This section gives a procedure for each type of actuator. Needed equipment: 1. A pressure regulator capable of providing a mid-scale input
SD74 176. Loosen the spring seats and adjust the zero screw for a 3 psig output. 7. Position the valve to its maximum stroke position. 8. Turn b
SD74 18On spring-loaded and cushion-loaded operators, only one of the positioner outputs is used; the other is plugged. The Model 74 is then a single
SD74 19 FIGURE 4-2 Motion Transmitter Schematic 5.0 MAINTENANCE A spring return pushbutton restriction cleaner is built into the body of the va
SD74 2TABLE OF CONTENTS SECTION AND TITLE PAGE 1.0 INTRODUCTION...
SD74 20 • Plungers – The plungers differ in shape, as shown in this figure. • Diaphragm Rings – The Model 74S diaphragm ring has a nozzle. The Mod
SD74 215.1 DISASSEMBLY If it is necessary to disassemble the positioner, refer to Parts List No. 12372PL and proceed as follows: 1. Remove the pi
SD74 225.2 ASSEMBLY To assemble, reverse the disassembly procedure and take into account the following: 1. Exercise care when installing the output
SD74 236.0 PARTS LIST Model Series 74 H/FR Valve Positioners Drawing No. 12372PL 11/94 Supersedes 1/88 IMPORTANT Service Parts Kits are availab
SD74 24 Symbol Part No. Description Req’d *1 6751-3 Sealing Spring 1 *2 6750-49 Plunger Spring 1 *3 See Table Plunger 2 5 12372-338 Exhaust
SD74 25Symbol Part No. Description Req’d 40 14923-52 Mounting Plate (not shown) As Req’d 41 14923-49 Enclosure (not shown) 1 A 1-026
SD74 3LIST OF ILLUSTRATIONS FIGURE AND TITLE PAGE 2-1 Installation Dimensions...
SD74 41.0 INTRODUCTION This instruction describes the installation, operation, and maintenance of the Model Series 74 Valve Positioner and Motion Tr
SD74 51.3 ORDERING RANGE AND SUPPRESSION SPRING KITS Order either a rectilinear spring kit or a rotary spring kit for each Model 74, depending upo
SD74 6 TABLE 1-1 Rectilinear Range Spring Kits, Continued INSTRUMENT INPUT PRESSURE RANGE IN PSIG ACTUATOR STROKE IN INCHES KIT AND PARTS 3-15 3-9 3
SD74 71.4 CUSTOMER/PRODUCT SUPPORT For support and the location of your local Siemens representative, refer to the table below for the URL of the
SD74 82.0 INSTALLATION See Figure 2-1 for mounting dimensions and connections. The two basic mounting positions of the positioner are normal, where
SD74 9 CAUTION Synthetic compressor lubricants in the air stream at the instrument may cause it to fail. The requirements for a quality instrument
Comentarios a estos manuales