P303 Pressure Regulator • Minimize Sudden Downstream Load Change • Wide Pressure Ranges • Integral Monitoring The BelGAS P303 and P303H gas pressure reducing regulators are available with a true monitor regulator, which acts independently of the main regulator. The monitor provides equivalent overpressure protection when compared to a standard two-regulator monitor setup. Should one regulator fail, the other regulator provides control and overpressure protections. The regulator's fast action reduces the risk of shock from abrupt changes in downstream conditions and can help to prevent safety equipment from causing unnecessary, expensive, and time-consuming operation shutdowns. Applications • Compressors • Gas Engines • Service Regulators P303 Series Maximum Inlet Pressure P303 Series Range Springs

How Does the P303 Series Work? Under normal operational conditions, the P303 Series performs as the P300. When there is a demand downstream of the regulator, the main valve disk moves away from the orifice to allow flow. The Monitor diaphragm and piston are always in motion based on outlet feedback though the pitot tube at the outlet. Secondary or monitor orifice & valve disk Main orifice & valve disk The monitor module will activate when the system experiences a failure such as the main valve disk is stuck open or the lever disengages from the valve stem assembly. When the P303 main regulator...

BelGAS P303 Part Number Selection Before attempting to select a BelGAS P303, several pieces of information should be known: port size, the supply pressure the unit operates at normally, the output pressure the unit operates at normally, the downstream flow requirement during normal operation, the maximum amount of output pressure the unit is allowed to have during an over pressurization situation, and the media the unit will be regulating. Example #1 Known Requirements 1.5 NPT 30 PSIG inlet 7" WC outlet under normal conditions 1500 SCFH 0.6 specifc gravity natural gas Should not rise above 1.3...

P303 Part MatrixP303 Version Normal High Pressure 02 03 0 Version Only H Version Only Port Size 1.5 NPT 1.5 x 2 NPT 2 NPT use with G1 Monitor use with G1 Monitor use with G2 Monitor use with R1, B1 Monitor use with S1 Monitor use with S2 Monitor Note: Monitor Rage should be chosen prior to choosing Main Spring Special Construction None 125FF (2” Iron Only) P303 Regulator Rebuild Kits Kit Includes Part Number Port Orientation Up (Standard) Down Right Left Bonnet Orientation 12 O'clock 3 O'clock (Standard) 6 O'clock 9 O'clock use with 06 or 85 Main Spring use with 14 Main Spring use with 28 Main...

•NOTE ORIENTATIONS IE AND 2E ARE NOT AVAILABLE WITH FLANGE BODY Body Size

Set Point: Maximum Allowable Supply Pressure, 7" WC Output Pressure, 5 SCFH Outlet Pressure, PSIG 30 40 Supply Pressue (PSIG) Set Point: Maximum Allowable Supply Pressure, 1 PSIG Output Pressure, 5 SCFH Outlet Pressure, PSIG 60 80 Supply Pressue (PSIG) Set Point: Maximum Allowable Supply Pressure, 2 PSIG Output Pressure, 5 SCFH Outlet Pressure, PSIG 60 80 Supply Pressue (PSIG) 0.375" Orifice

P303 Flow Capacities in SCFH (Nm3/h) of 0.6 Specific Gravity Natural Gas Outlet Pressure, Spring Part Number, and Accuracy Inlet Pressure Orifice Size, Inches (mm) 1. Limited due to boost - Shaded areas show where indicated droop would be exceeded regardless of capacity. - Shaded areas show where maximum operating inlet pressure for a given port diameter is exceeded.

P303 Flow Capacities in SCFH (Nm3/h) of 0.6 Specific Gravity Natural Gas Outlet Pressure, Spring Part Number, and Accuracy Inlet Pressure Orifice Size, Inches (mm) 1. Limited due to boost - Shaded areas show where indicated droop would be exceeded regardless of capacity. - Shaded areas show where maximum operating inlet pressure for a given port diameter is exceeded. 8

P303 Flow Capacities in SCFH (Nm3/h) of 0.6 Specific Gravity Natural Gas

Interchangeability between the BelGAS P203 series and the P303 series The unique feature about the BelGAS P303 regulator is that it utilizes the BelGAS P203 series bodies using a simple adaptor ring. The simplicity of down-sizing a system when a BelGAS P203 unit is installed is as easy as removing the 2 body-to-head bolts and installing a BelGAS P303 head with the appropriate adaptor and bolts. Or, if a 1.5” x 2” or 2” x 2” BelGAS P303 is installed, the BelGAS P303 head can be removed and a BelGAS P203 head installed to up-size your system. It is important to know, a P303 head can be mounted...