What does PSI and PBW in SAP stands for what are their differences?

Possibly "per square inch."

i dont know the answer

System Application Program

PSI stands for Pounds Per Square Inch.

Among other things, it may refer to a non-standard (non-SI) unit of pressure, "pounds per square inch". Psi is a Greek letter in the Greek alphabet (uppercase Ψ) (lowercase ψ). When it is used in...