The outlet pressure of a reciprocating compressor ranges from 25 MPa to 28 MPa, and the measurement error should not be greater than 1 MPa. The technology requires on-site observation and alarm at high and low limits. A pressure gauge should be determind accuracy and measurement range should be pointed out. (The range of YX-150 pressure gauge is 0-10,0-16, 0-25, 0-50,0-60 MPa)