Instrumentation

DOE-HDBK-1016/1-93 ENGINEERING FLUIDS DIAGRAMS AND PRINTS Engineering Fluid Diagrams and Prints The diagram may also depict Figure 8 More Piping Symbols the individual fittings comprising the piping runs depending on its intended use. Figure 8 shows symbols used to depict pipe fittings. Instrumentation One of the main purposes of a P&ID is to provide functional information about how instrumentation in a system or piece of equipment interfaces with the system or piece of equipment. Because of this, a large amount of the symbology appearing on P&IDs depicts instrumentation and instrument loops. The symbols used to represent instruments and their loops can be divided into four categories. Generally each of these four categories uses the component identifying (labeling) scheme identified in Table 1. The first column of Table 1 lists the letters used to identify the parameter being sensed or monitored by the loop or instrument. The second column lists the letters used to indicate the type of indicator or controller. The third column lists the letters used to indicate the type of component. The fourth column lists the letters used to indicate the type of signals that are being modified by a modifier. PR-02 Rev. 0 Page 8