Arrive on time. It's important that you are on-time for an interview. By doing so, you're showing that you are mindful and respectful of the interviewer's time. Arriving late can negatively impact your chances of landing the job, as it shows a sense of apathy and indifference.
There are two types of lever machines; manual piston and spring piston design. With the manual piston, the operator directly pushes the water through the grounds. In the spring piston design, the operator works to tension a spring, which then delivers the pressure for the espresso (usually 8 to 10 bar; 116 to 145 psi). Steam-driven A steam coffee machine
2.20632 Bar. Psi : Psi is the abbreviation of pound per square inch, and is widely used in British and American. 1 psi = 6,894.76 Pascals. Bar : The bar is a unit of measurement for pressure. It is widely used in the daily life particularly in European countries, though that is a non-SI unit. 1 bar is equal to 100,000 Pascals, which is close approximately to atmospheric pressure, so it is often used to represent atmospheric pressure rather than standard atmosphere (101325 Pascals).