To properly calculate the differential pressure required for the pressure differential shutoff (CDHS-3), what must you identify first?

To determine the differential pressure required for the pressure differential shutoff (CDHS-3), it is essential to identify the orifice plate bore size first. The orifice plate bore size directly influences the flow characteristics of the fluid passing through the system, affecting the pressure differential readings.

Knowing the bore size allows for accurate calculations of the flow rate and the pressure drop across the orifice plate. These measurements are crucial in ensuring that the system operates effectively and that the differential pressure shutoff can respond appropriately under varying conditions. Without this foundational information about the orifice plate size, subsequent calculations regarding upstream and downstream pressures may not yield accurate or usable results.

Thus, the focus on the orifice plate bore size underscores its critical role in the overall assessment and functioning of the pressure differential shutoff system within water and fuel systems.