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1. DESIGN OBJECTIVES <br />1.1. Provide the generator with a stable gas supply <br />pressure over varying gas flow demand conditions. <br />Maximum gas flow for all Generac generators are <br />listed on the unit nameplate and generator data <br />sheets.2 <br />1.2. The pressure difference measured at the <br />generator fuel pressure test port should typically be <br />less than 2" water column (w.c.) from no-load running <br />to full-load running condition. <br />1.3. The gas pressure must remain above the <br />minimum specified for the generator set at all times, <br />under all operating conditions. Failure to maintain <br />adequate gas pressure and flow will result in <br />operational problems such as extended crank cycles, <br />inability to carry full load, and unstable engine speed. <br />Natural Gas Supply System Design Guide for Generac Industrial Spark Ignited Generators <br />Figure 1: Typical natural gas supply regulator and piping configuration. <br />1.4. Maintain a pressure and flow margin to allow for <br />seasonal pressure variation on the upstream gas <br />system. The emergency system must be before the <br />facility shutoff. <br />1.5. Other facility loads must be factored in while <br />sizing the Generator fuel system. It is recommended <br />that the generator should have a dedicated fuel <br />supply, which is not shared with any other <br />appliances (furnace, water heaters, ranges, etc.) and <br />the Generator fuel supply line shall be installed away <br />from a high heat source so that the fuel temperature <br />must remain at an acceptable operating rage. <br />2.1. Regulator Body Size: The inlet and outlet ports <br />on a regulator are typically a single metal casting. The <br />“body size” refers to the nominal diameter of the inlet <br />and outlet pipe threads (or flange). <br /> <br />The regulator body size should never be larger than <br />the pipe size, but it may be smaller provided the <br />required flow can be obtained through the <br />smaller regulator body size. <br />CONTINUED | 2 <br />2. REGULATOR PERFORMANCE ATTRIBUTES3 <br />Primary Fuel Pressure Regulator <br />Flex Hose Base Rail <br />Fuel Shut Off <br />Fuel Pressure Test Port <br />Sediment Trap <br />High Pressure (psi) <br />Natural Gas <br />Primary fuel pressure regulator no less than 10 feet of pipe length from the generator set connection point <br />Docusign Envelope ID: 2F58BEE5-DDBE-42EB-8DFA-5E2508488B04